the nurse practitioner workforce in six countries: size ... · in order to assess the potential of...
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The Nurse Practitioner Workforce in Six Countries: Size,
Growth, Physician Substitution Potential
Journal: BMJ Open
Manuscript ID bmjopen-2016-011901
Article Type: Research
Date Submitted by the Author: 14-Mar-2016
Complete List of Authors: Maier, Claudia; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing; Technische Universitat Berlin, Department of Healthcare Management Barnes, Hilary; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing Aiken, Linda; University of Pennslvania, Center for Health Outcomes and Policy Research, School of Nursing Busse, Reinhard; Technische Universität Berlin, Department of Health Care
Management
<b>Primary Subject Heading</b>:
Nursing
Secondary Subject Heading: Global health
Keywords: nursing, health workforce, physicians, PRIMARY CARE
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The Nurse Practitioner Workforce in Six Countries: Size, Growth, Physician
Substitution Potential
Corresponding author: Claudia B Maiera) b), MSc
a) Harkness & B. Braun Fellow in Healthcare Policy and Practice
Center for Health Outcomes and Policy Research
University of Pennsylvania, School of Nursing
Claire Fagin Hall
418 Curie Blvd
Philadelphia, PA 19104-4217; b) Department of Healthcare Management,
Technische Universität Berlin, Germany
Administrative office H80
Str. des 17. Juni 135
10623 Berlin, Germany
Phone: +49 176 32944628
Fax: +49 30 314 28433
Hilary Barnes, PhD, CRNP
Postdoctoral Research Fellow
Center for Health Outcomes and Policy Research
University of Pennsylvania
418 Curie Blvd
Claire M. Fagin Hall, 388R
Philadelphia, PA 19104-4217
Phone: +1 215-898-4908
Fax: +1 215-573-2062
Linda H Aiken, PhD, RN
Claire M Fagin Professor and Director
Center for Health Outcomes and Policy Research
University of Pennsylvania
418 Curie Blvd
Claire M. Fagin Hall, 387R
Philadelphia, PA 19104-4217
Phone: +1 215-898-9759
Fax: + 215-573-2062
Reinhard Busse, PhD, MD, MPH, FFPH
Head of the Department of Health Care Management
Faculty of Economics and Management
Head of the Berlin hub of the European Health Observatory on Health Systems and Policies
Technische Universität Berlin
Administrative office H80
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Str. des 17. Juni 135
10623 Berlin, Germany
Phone: +49 30 314 28420
Fax: +49 30 314 28433
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ABSTRACT
Objectives. Many countries are facing provider shortages in primary care or are projecting
shortfalls for the future. In order to assess the potential of Nurse Practitioners (NP) in
alleviating shortages and expand access, we analyzed the size, annual growth (2005-2015),
and the extent of advanced practice of NPs in six Organisation for Economic Cooperation and
Development (OECD) countries.
Design. Cross-country data analysis of national nursing registries, regulatory bodies, and
statistical offices data; as well as OECD health workforce and population data.
Setting/Participants. NP and physician workforces in six OECD countries (Australia,
Canada, Ireland, Netherlands, New Zealand, United States).
Primary and secondary outcome measures. The main outcomes were the absolute and
relative number of NPs per 100,000 population compared to the nursing and physician
workforces; the Compound Annual Growth Rates (CAGR), annual and median percentage
change from 2005-2015; and the extent of advanced clinical practice measured by physician
substitution effect.
Results. The United States showed the highest absolute number of NPs and rate per
population (40.5 per 100,000 population), followed by the Netherlands and Canada (12.6 and
9.8), Australia (4.4), and Ireland and New Zealand (3.1, respectively). Annual growth rates
were high in all countries, ranging from annual compound rates of 6.1% in the United States
to 27.8% in the Netherlands. Growth rates were between three- and nine-times higher
compared to physicians. Finally, empirical studies suggested that NPs are able to provide 67-
90% of all primary care services.
Conclusions. NPs are a rapidly growing workforce with high levels of advanced practice
holding future potential to filling gaps or shortages, particularly in primary care. Workforce
monitoring based on accurate data is critical to inform educational capacity and workforce
planning. Including routine data in international workforce databases would improve data
availability globally.
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Strengths and limitations of this study
• This is the first international study to determine the total and relative size of Nurse
Practitioners per 100,000 population in comparison to physicians in six OECD
countries.
• A strength of this study is the analysis of comprehensive and largely unexplored data
from authoritative sources in the six countries.
• Annual growth rates were calculated for 2005-2015 using compound annual growth
rates (CAGR), annual and median percentage changes, to account for excessive yearly
changes found.
• The study faces limitations as to data variability of the activity levels of NPs and
physicians, yet, for within-country comparisons, we used consistently the same
activity levels for NPs and physicians.
• While there is limited empirical research on the substitution effect of NPs for
physicians in the six countries studied, findings show that NPs work at high levels of
advanced practice.
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BACKGROUND
Health workforce shortages and geographical imbalances exist in many countries worldwide
(1). The World Health Organization has estimated a deficit of 7.2 million health professionals
globally (2). The United States (U.S.) projected a shortfall of 44,000 primary care physicians
by 2035 (3) and the European Commission has estimated a shortage of 1 million health
professionals by the year 2020 (4). While educating more physicians is one workforce
strategy, countries are also investing increasingly in a highly qualified nursing workforce,
such as Advanced Practice Nurses or Nurse Practitioners (APN/NP), with usually Master’s
level education (5). Expanding the roles of nurses combined with task-shifting from
physicians to nurses as suggested by the World Health Organization, has received policy
attention to respond to shortages (6, 7).
There is a consistent body of evidence showing that nurses with advanced education can
provide high-quality care that is comparable to physicians for a range of acute and chronic
illnesses (8-11). The U.S. was the first country to introduce NPs in 1965, followed by Canada
in 1967 (12, 13). Other countries have more recently introduced NPs, including the United
Kingdom (U.K.), Ireland, the Netherlands, Australia and New Zealand (14-18).
The extent to which NPs are effective in addressing shortages depends on the scale of this
workforce, and its integration and implementation in healthcare (19). Scale in this context
refers to two factors, a sufficient numerical size of NPs and the extent of advanced practice.
Both elements are critical to assess the contribution of the workforce.
Few international research exists on the size of the NP workforce. The international literature
has compared primarily NP education, governance and regulation of titles (20-24). In an
overview of the primary care workforce in six countries, the total number of NPs was found to
be low in most countries (25). However, the study only provided the total number of
providers, no further information on its relative size compared to other professions or time
trends. At the individual country-levels, many studies exist, particularly in the U.S. that aim to
quantify the total number of NPs, by employment, specialty and clinical practice area (26-29).
They found that the various data sources provide a patchy overview in the U.S., particularly
when focusing on the clinically active NPs and specialty areas (26). The comparatively fewer
studies on the size of NPs in Canada, Australia, and New Zealand found that the workforce is
small, but provided limited information beyond the number of providers (30, 31).
While NPs perform a substantially expanded range of clinical services, there is limited
knowledge on the detailed level of advanced practice. Conceptually, the substitution effect of
physicians by NPs refers to the quantification of how many patients or services in a particular
care setting can be performed by NPs that are usually provided by physicians (32, 33). In a
systematic review, 30-70% of clinical activities of physicians were found could be taken over
by NPs, however, most of the included studies were conducted in the 1970s and 1980s (32).
NPs’ roles have expanded internationally, hence an update of the literature is relevant to
estimate the extent of advanced practice and variations across countries.
This is the first study to assess the scale of NPs, growth rates and the extent of advanced
practice compared to physicians, using a cross-country comparative study design. The study
pursued the following three research questions: 1) to analyze the absolute and relative size of
the NP workforce in six OECD countries (Australia, Canada, Ireland, the Netherlands, New
Zealand, and the U.S.), focusing on practicing NPs, their proportion of the total nursing
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workforce and rates per 100,000 population relative to the physician workforce; 2) to examine
time trends from 2005-2015 in the NP compared to the physician workforces; and 3) to
estimate the extent of advanced practice in primary care measured by a concept referred to as
physician ‘substitution effect’.
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METHODS
Definitions and outcome measures
In order to assess the absolute and relative size of the NP workforce, we followed the OECD
definition of activity levels of health professions: (i) practicing professionals (providing direct
patient care), (ii) professionally active (providing direct patient care, plus working in related
administration, management or research as part of the profession), and (iii) registered/licensed
to practice (authorized to practice, including practicing, professionally active and non-
practicing providers) (34). For this study, the activity status practicing NPs was preferred over
professionally active and registered/licensed, following the OECD (34). In countries with no
available information on the number of practicing NPs, data on professionally active or
registered was used.
To analyze time trends, we compared the yearly growth rates of NPs to physicians from 2005
to 2015 where available. We chose the physician profession as comparator for two reasons.
First, to compare the growth rates to estimate the potential in alleviating physician shortages
and second, since OECD data on time trends are of better quality and comparability than
those for the nursing profession.
To answer the research question on NPs levels of advanced practice, we performed a literature
scoping review, following the concept referred to as ‘substitution effect’, which estimates the
potential of a new, extended professional role in taking up activities of an established
profession (32).
First phase: identification of countries and data availability - the TaskShift2Nurses
Study
We identified countries with APN/NPs based on an expert survey in 39 industrialized
countries (Task-Shift2Nurses Study 2015). Information on the survey itself, its sampling
strategy, data collection and analysis is provided elsewhere (forthcoming, (23)). A total of 93
country experts participated (response rate 85.3%). The survey included questions on scope of
practice and education, data availability, existence of nursing registries, and mandatory vs.
voluntary registration policies, among others. Institutional Review Board (IRB) approval was
obtained at the University of Pennsylvania.
The TaskShift2Nurses study identified eleven countries with APN/NPs: Australia, Canada,
Finland, Ireland, Netherlands, England, Northern Ireland, Scotland, Wales, New Zealand and
the U.S (23). Definitions used were existence of APN/NPs, education at APN/NP level and
advanced practice focusing on primary care, measured by seven clinical activities: authority to
prescribe medications, ordering medical tests, decide on medical treatment,
diagnosis/advanced health assessment, referrals, responsibility for a panel of patients, and first
point of contact (5).
For the purpose of this study, in a subsequent step we contacted country experts individually
to obtain further information on data sources and holders. The countries within the United
Kingdom and Finland were excluded from this study, because no registry data or other
national or subnational data sources on APN/NPs were identified.
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Second phase: country-specific secondary data collection
In a subsequent step, we retrieved secondary data on NPs for the remaining six countries from
authoritative sources as advised by country experts. All six countries had NPs or similar roles
working in advanced practice, of which the titles were regulated and registration was
mandatory. The secondary data collection phase took place between August 2015 and January
2016. These sources included nursing boards or councils (Australia, Ireland, New Zealand),
an institute on health information (Canada), and a nurse specialist registry
(Registratiecommissie Specialismen Verpleegkunde, RSV) in the Netherlands. In the
Netherlands, Nurse Specialists (Verpleegkundig Specialisten) are sometimes referred to as
NPs in English literature (15), however, we decided to keep the translation closest to its
original title, since this title is regulated.
In the U.S., several data sources were reviewed for suitability, including data from the Kaiser
Family Foundation (KFF) (35), American Association of Nurse Practitioners (AANP) (36),
and the U.S. Bureau of Labor Statistics (37-39). Challenges of the U.S. data include the co-
existence of multiple sources which calculate the workforce differently. The KFF provided
data on professionally active NPs based on active state NP licenses, however, no data on time
trends were available. The AANP data cover NPs licensed to practice; however, these data are
estimated and actual numbers not available to the public. The U.S. Bureau of Labor Statistics
estimates the professionally active NP workforce, but NP-specific data are only available
since 2012 and exclude self-employed NPs (37-39). We chose for each of the research
questions the most accurate data source highlighting their strengths and weaknesses.
Canada and New Zealand had data on time series available for all years since 2005, whereas
the Netherlands had data since 2009, the year of introduction of the specialist registry, Ireland
since 2010 and Australia since 2012.
Third phase: literature review on the extent of advanced practice
In addition to the secondary data analysis, we conducted a comprehensive literature review,
covering Medline, CINAHL, Google Scholar, and grey literature, to identify studies on
substitution effect/extent of advanced practice. Studies were included if they used the a
method to quantify the extent of advanced practice, also referred to as physician “substitution
effect”, defined as the percentage of typical physician-provided activities that can be officially
and safely performed by NPs or the percentage of all services that can be safely provided by
NPs (32, 40). Search terms included various combinations of the terms substitution, nurse
practitioner, extent of advanced practice, scope of practice, among others. The search was
conducted in English, plus we contacted country experts for additional, grey literature.
Inclusion criteria were studies conducted in one of our six countries that empirically analyzed
the extent of advanced practice of NPs compared to physicians or percentage of all services
that were provided by NPs.
Data analysis
Regarding research question 1, we calculated NP rates per 100,000 population using the
population sizes provided by the OECD 2015 population statistics online database (41). To
compare the density of NPs with physicians, we retrieved the physician ratios per 1,000 from
the OECD database, which we subsequently multiplied by 100 to obtain rates per 100,000
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population (42). Data on the nursing workforce was retrieved from the same data holders from
which the data on NPs were obtained, except for the Netherlands where nurse specialists are
registered in a separate registry (43).
As for research question 2 on time trends, we calculated the yearly percentage change of NPs
and physicians (e.g. 2005-06, 2006-07), covering 2005 to 2015 or years available, to assess
the relative growth of the APN/NP profession compared to the physician profession.
Percentage change is a method derived from demographics (44). It is based on the calculation
of the absolute difference at two points in time and divided by the original group size,
multiplied by 100. This method allows to quantify the increase or decrease over time periods
irrespective of groups’ differences in size. In addition to yearly percentage changes, we
calculated the Compound Annual Growth Rates (CAGR) which is commonly used in
comparison of time trends (45-47), since it smoothes yearly growth rates over time. In
addition, we calculated the average and median percentage change across the entire time
period for each of the country and profession covered (34).
Regarding research question 3, all studies identified from the literature scoping review were
reviewed according to inclusion and exclusion criteria. Studies were included if the concept of
substitution was applied calculating the percent of substitution effect, provided the study was
implemented in one of the six countries. We subsequently extracted the numerical results of
the percentage of all services that NPs were able to provide or percentage of physician
services that could be taken over by NPs, depending on the service delivery setting and
location, but focusing on primary care. We excluded simulations or projections of the
potential substitution effect.
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RESULTS
Total and relative size of the Nurse Practitioner workforce
The United States showed the largest number of professionally active NPs (N= 174,943)
compared to the other five OECD countries, which represented 5.6% of its total active U.S.
nursing workforce in 2015 (35) (Figure 1). In the Netherlands and Canada, both the total and
relative size was lower, percentages were 1.5% and 1.3% respectively, based on data on
registered NPs in the Netherlands and practicing NPs in Canada. In Australia, New Zealand
and Ireland, the relative sizes were very small, 0.5% and less.
[Figure 1: Total number of NPs and % of professional nursing workforces, 2015*]
Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following secondary data
sources: (35, 43, 48-52),
Notes: *2015: except for Canada, Ireland: 2014; Data on RNs include NPs, U.S.=United States, NP= Nurse
Practitioner, N=total number, P=Practicing, PA=Professionally Active, R=Registered/Licensed to practice,
RNs=Registered Nurses, Caveats: Netherlands (nurse specialists): an estimated 12 test accounts are in the
database (0.4%) that cannot be filtered out (personal communication, with registry advisor at Verpleegkundig
Specialisten Register, 29 January 2016).
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Results regarding the workforce density per population showed similar patterns across the six
countries (Figure 2). The rate of NPs in the United States was highest, at 40.5 practicing NPs
per 100,000 population (41, 53) based on 2012 data to allow for comparisons with physicians.
NPs were less than one fifth of the U.S. physician workforce (41, 42).
In the Netherlands and Canada, rates were considerably lower compared to the U.S. at 12.6
and 9.8 per 100,000 population. Compared to physicians, Australia, Ireland and New Zealand
showed very low rates.
[Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*]
Sources: Authors’ calculations, based on the following data sources: (35, 48-53), Data on physicians based on
OECD 2015 database (42)
Notes: *Year 2013; except for Ireland (2014), United States (2012) depending on years covered by OECD
physician data; NPs= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active,
R=Registered/Licensed to practice, U.S.=United States, Caveats: Netherlands (Nurse specialists): an estimated
12 test accounts are in the database that cannot be filtered out (personal communication, with registry advisor at
Verpleegkundig Specialisten Register, 29 January 2016).
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Growth of the Nurse Practitioner workforce from 2005-2015
All countries showed a continuous growth of their NP workforce from 2005 to 2015 or those
years available (Table 1). However, growth rates varied considerably across countries; and
within countries between NPs and physicians.
In the U.S., NPs licensed to practice increased from an estimated 106,000 in 2004 to 192,000
in 2014 (36). Rates per 100,000 population increased from 35.87 to 60.22 NPs per 100,000
population. Data on professionally active NPs showed an increase from 105,780 to 122,050
NPs, yet were only available from 2012 to 2014 (37-39).
In the Netherlands, the numbers of Nurse Specialists registered increased rapidly, from 140 in
2009 to 2,749 in 2015. The rate of Nurse Specialists per 100,000 population in the
Netherlands showed the most rapid increase of all countries studied, more than 14-fold, from
0.85 Nurse Specialists in 2009 to 14.74 Nurse Specialists per 100,000 in 2014.
In Canada, the rate of NPs per 100,000 increased from 2.9 in 2005 to 10.7 in 2014, more than
three-fold. In Australia, the NP rate increased from 3.5 in 2012 to 5 per 100,000 population in
2014. Although a rapid increase took place in New Zealand from 0.3 in 2005 to 3.1 in 2014,
and in Ireland from 0.8 in 2010 to 3.1 in 2014, total numbers remained at low levels.
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Nurse Practitioner compared to physician growth rates
We present compound annual growth rates (CAGR), and the median percentage changes over
the 2005-2015 period to show differences in the calculation methods (table 2). In order to
account for the extremly high growth rates in the first year in the Netherlands and Ireland due
to the small numbers (Netherlands: 2009-10, Ireland: 2010-11), we calculated the CAGR for
the full period and the CAGR without the first year for the two countries.
Growth among NPs was high in all countries, and consistently and considerably higher than
among physicians. The compound growth rate among Nurse Specialists in the Netherlands
was 27.8% (CAGR 2010-2015), the highest of all six countries. The yearly growth was higher
than that of its medical workforce at 2.9%, overall yearly growth was more than 9-times
higher. In New Zealand and Canada, compound annual growth of NPs was 27.3% and 16.7%
respectively, approximately nine- and five-times higher than that of their medical workforces
(2.8%, and 3.3%). Ireland showed a comparatively lower yearly increase of its NP workforce,
yet, still a more than four-times growth compared to its physician workforce. Of the six
countries, the United States had the lowest annual compound growth of 6.1% or 7.4%
annually depending on the data sources, yet, was still more than three-times higher than that
of physicians (36-39, 41, 42).
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Table 1: Total number of Nurse Practitioners and Physicians, six countries, 2005-2015 (or years available)
Sources: authors’ calculations, based on the following data sources (36-39, 42, 48-52, 54-63),
Notes: NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats: United States: *data on
professionally active Nurse Practitioners do not include self-employed, hence underestimate totals (37), ^year 2004 (in lieu of 2005 data availability) e= data on registered NPs are estimates, exact
numbers are not publicly available (36), Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot
be filtered out (estimated 8 cases yearly in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January
2016), Canada: OECD data on MDs, based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010, due to change of data holders. (64, 65)
Year United States Canada Netherlands Australia New Zealand Ireland
NP NP MD NP MD NS MD NP MD NP MD NP MD
PA R R PA PA R R R R R R PA PA
2005 .. 106,000e^ 902,053 943 69,619 .. 55,673 .. 67,890 14 11,555 .. ..
2006 .. .. 921,904 1,129 70,870 .. 57,098 .. 71,740 21 11,889 .. 11,617
2007 .. 120,000e 941,304 1,344 72,903 .. 58,661 .. 77,193 30 12,318 .. 12,311
2008 .. .. 954,224 1,626 75,155 .. 60,300 .. 78,909 46 12,746 .. 13,022
2009 .. 130,000e 972,376 1,990 78,623 140 62,057 .. 82,895 50 13,176 .. 13,663
2010 .. 140,000e 985,375 2,486 80,895 807 63,585 .. .. 72 13,398 38 14,029
2011 .. 148,000e 1,004,635 2,777 84,313 1,272 65,568 .. 87,790 91 14,021 97 14,814
2012 105,780* 157,000e 1,026,788 3,157 87,306 1,847 68,119 788 91,504 103 14,280 109 14,498
2013 113,370* 171,000e 1,045,910 3,477 90,205 2,124 69,942 1,004 91,467 117 14,596 123 14,054
2014 122,050* 192,000e .. 3,786 .. 2,480 .. 1,165 .. 138 14,787 141 14,016
2015 .. .. .. .. .. 2,749 .. 1,214 .. 157 .. .. ..
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Table 2: Annual growth of the nurse practitioner and physician workforces, measured by yearly percentage change (%), median percentage change
and Compound Annual Growth Rate (CAGR, %), in six countries, 2005-2015 (or years available)
Sources: authors’ calculations, based on the following data sources (36-39, 42, 48-52, 54-63)
Notes: CAGR=Compound Annual Growth Rate, [1]=CAGR (2004/2015) calculated based on 2004-2014 data (2004 data used in lieu of missing 2005 data) [2]=CAGR (2010-2015), 2009-10 was
excluded due to excessive growth rate caused by small numbers (CAGR 2009-2015: 64.3%, not shown), [3]=CAGR (2011-2014), 2010-11 data excluded (CAGR 2010-14: 38.8%, not shown),
PC=Percentage Change, NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats:
United States: *data on professionally active Nurse Practitioners do not include self-employed (37). °Data on registered NPs are estimates, exact numbers are not publicly available (36),
Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot be filtered out (estimated 8 cases yearly
in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January 2016), Canada: OECD data on MDs,
based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010,
due to change of data holders. (64, 65)
Year United States Canada Netherlands Australia New Zealand Ireland
NP NP MD NP MD NS MD NP MD NP MD NP MD
PA* R° R PA PA R R R R R R PA PA
2005-2006 .. ..^ 2.2% 19.7% 1.8% .. 2.6% .. 5.7% 50.0% 2.9% .. ..
2006-2007 .. .. 2.1% 19.0% 2.9% .. 2.7% .. 7.6% 42.9% 3.6% .. 6.0%
2007-2008 .. ..^ 1.4% 21.0% 3.1% .. 2.8% .. 2.2% 53.3% 3.5% .. 5.8%
2008-2009 .. .. 1.9% 22.4% 4.6% .. 2.9% .. 5.1% 8.7% 3.4% .. 4.9%
2009-2010 .. 7.7% 1.3% 24.9% 2.9% 476.4% 2.5% .. .. 44.0% 1.7% .. 2.7%
2010-2011 .. 5.7% 2.0% 11.7% 4.2% 57.6% 3.1% .. .. 26.4% 4.6% 155.3% 5.6%
2011-2012 .. 6.1% 2.2% 13.7% 3.5% 45.2% 3.9% .. 4.2% 13.2% 1.8% 12.4% -2.1%
2012-2013 7.2% 8.9% 1.9% 10.1% 3.3% 15.0% 2.7% 27.4% 0% 13.6% 2.2% 12.8% -3.1%
2013-2014 7.7% 12.3 .. 8.9% .. 16.8% .. 16.0% .. 17.9% 1.3% 14.6% -0.3%
2014-2015 .. .. .. .. .. 10.9% .. 4.2% .. 13.8% .. .. ..
Median PC 7.5% 7.7% 2% 19.0% 3.2% 30.1% 2.8% 16.0% 4.7% 22.2% 2.9% 13.7% 3.8%
CAGR 7.4% 6.1%[1] 1.9% 16.7% 3.3% 27.8%[2] 2.9% 15.5% 5.1% 27.3% 2.8% 13.3%[3] 2.4%
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Extent of advanced clinical practice
The five studies identified that quantified the extent of clinical practice of NPs were
conducted in the U.S., Canada and the Netherlands (Table 3). No studies conducted in the
three other countries were identified. The five studies found NPs able to provide between 67%
and 90% of primary care services. Differences existed within and across countries, suggesting
that within countries, service delivery settings, rural versus non-rural areas, education and
practice profiles may play a role. Most studies were based on small sample sizes and/or
conducted more than 30 years ago (66-68), whereas one recent studies with a larger sample
size was identified (29).
Table 3: Level of advanced clinical practice, measured by physician “substitution” effect
of nurse practitioners
Country Extent of advanced practice (% of all services or % of
physician substitution effect)
Sources
Australia n/a
Canada 67% of all primary care patient visits provided by NPs
(66)
Ireland n/a
New Zealand n/a
Netherlands 75-83% of clinical activities in out-of-hours primary
care settings (weekend shifts in GP practices) could be
taken over by Nurse Specialists (Verpleegkundig
Specialist)
(68, 69)
United States 75% of adult primary care can be provided by NPs
90% of pediatric primary care can be provided by NPs
75% of primary care visits in rural settings
(67)
(29)
Sources: provided in table
Notes: n/a= not available (no relevant studies identified)
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DISCUSSION
The size of the NP workforce in the six countries studied is variable, but growing rapidly,
with high levels of practice in primary care. The U.S. is the only country where the NP
workforce has reached a considerable density of 40.5 practicing NPs per 100,000 population,
in other countries the workforce is smaller, ranging from 12.6 per 100,000 population in the
Netherlands to low levels in New Zealand and Ireland. Yet, the workforce has rapidly and
consistently grown since 2005 in all countries, at much higher rates than the physician
workforce. Moreover, empirical studies show the large and wide range of advanced clinical
activities that NPs can provide. Depending on the country, provider models and settings, the
studies suggest that between 67 and 90% of primary care services can be safely provided by
NPs. Taken together, the findings demonstrate that the NP workforce has a high future
potential in filling unmet care needs and alleviating shortages in primary care.
Our study is the first of its kind to analyze the size and rate of NPs across six countries, and
set yearly growth in comparison with physicians. Yet, the study also faces several limitations.
First, data sources varied in the activity levels covered, e.g. practicing, professionally active
or registered NPs and physicians, which limits cross-country comparability. This limitation is
faced by all international data on health workforces, including the OECD and WHO, since
countries use different registration policies and data collection methodologies. However, for
within-country comparisons, we consistently compared the same activity levels of NPs and
physicians. In the U.S. decentralized approach to licensing of NPs, several different data
sources and holders were identified, with large differences across data in terms of size, active
levels and overall quality of data. Due to state-level authority over licensing procedures, data
may include double counting of NPs. Moreover, data on time trends of ten years were based
on estimates and covered the licensed workforce. Hence, the U.S. data can at best be
approximations to the actual number of practicing NPs over the ten-year period.
Our results are largely in line with one international study showing the relatively small scale
of the NP workforce (25). Reasons for the differences between the scale of the NP workforce
in the U.S. and other countries have not been empirically validated. It is assumed they may be
multifactorial. Not only the years of existence may play a role, as the U.S. was the first
country to implement NPs in 1965, but other factors may also influence their size and growth.
Canada introduced the first NPs only two years later, but relies on a much lower total number
and density of NPs than the U.S. Reasons for a small NP base in Canada have been discussed,
and include limited role clarity, differences across provinces and territories in education, and
challenges in creating positions for NPs (13, 30, 70). In Australia, NPs got access to the
Medical and Pharmaceutical Benefits Scheme in 2010, easing their practice, yet there are still
a number of policies impacting scope of practice (71, 72). Reasons for the low numbers in
New Zealand and Ireland include a younger existence of NPs dating back to the 2000s, and
high entry-level requirements (14, 56, 73, 74).
Time series data showed a considerable increase of NPs in all countries studied, much higher
yearly growth than found in the medical workforces. This trend may partially but not entirely
be related to the fact that increases in very small numbers result in large growth rates. We
took account of this by excluding extreme values from the CAGR calculations for Ireland and
the Netherlands, and calculated median percentage changes which were comparable to
CAGR.
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The continuous and higher growth rates point to an emerging NP workforce that has not
reached its full numerical potential, as compared to professions with a longer tradition, such
as the physician workforce. Many countries in our study have removed or eased regulatory
barriers to advance practice, such as in Australia, which granted NPs’ access to the
pharmaceutical and medical benefits scheme in 2010 (75). New Zealand expanded
prescriptive authority for NPs in 2014 (76)), and the Netherlands has regulated the Nurse
Specialist profession in 2009 and expanding scope of practice in 2012 (77). In the U.S., an
increasing number of states have removed regulatory barriers over the last decade (78).
Moreover, medical student intake or residency places are restricted by some sort of quota
system or numerus clausus in all countries, to avoid an excessive medical workforce and at
the same time, physician shortages (79). These regulatory measures may explain the moderate
annual increase among the medical workforce. To which extent countries’ workforce planning
take account of NPs or other APNs to project student intake, has received little attention in
research and practice.
Our findings on the level and extent of advanced practice show that NPs could covered a
range of approximately 67 to 90% of all primary care services. Findings are largely in line
with a report by the American College of Physicians, suggesting that 60-90% of primary care
can be provided by NPs (80). Our findings confirm and suggests that NPs scope of practice
may have expanded compared to a previous review, that showed a lower range of 30% to 70%
of physician-provided activities that could be taken over by NPs (32).
This study shows a rapid yearly increase of the NP workforce, which suggests more attention
should be paid to its future potential to expand capacity and alleviate shortages. To date, data
on the NP workforce is not covered in international health workforce databases, neither by
WHO or OECD, nor the international or European nursing associations. Most data is publicly
available or available upon request from the respective nursing regulatory bodies’ websites or
other data holders.. In the United States with the numerically largest workforce, data
availability is limited, a barrier for the monitoring of the workforce. Integrating NPs in health
workforce data and intelligence systems at national and international level is therefore critical
for their development, education and deployment.
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CONCLUSIONS
Nurse Practitioners are a rapidly growing workforce internationally. If growth rates continue,
this workforce will increase considerably in the future and holds potential in alleviating
physician shortages or reducing waiting time, particularly in primary care. To date, NPs are
not included in international workforce databases, hence, the overall size of the workforce and
changes over time go unnoticed. Yet, data are available for NPs in most countries as
registration is mandatory. As this workforce grows, using routine data will become critical to
monitor NPs as part of the overall health workforce, in order to inform educational capacity,
workforce projections and planning.
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a) Contributorship statement
CBM had the main role in the study design, data collection, and analysis, and wrote the
manuscript. HB contributed to the identification of U.S. data and the literature review, and
was involved in the revisions of the manuscript. LHA and RB gave overall guidance on the
study, the methodology, and reviewed the paper. All authors read, commented upon, and
approved the final manuscript.
Acknowledgements: We are grateful to the Dutch Registration Commission for Nurse
Specialists in the Netherlands (Registratiecommissie Specialismen Verpleegkunde, RSV) for
their support in providing time series data and important additional contextual information.
Moreover, we thank the 93 country experts who participated in the survey. In particular, we
thank the following country experts for providing additional information on secondary data
sources: Julianne Bryce, Australian Nursing and Midwifery Federation; Miranda Laurant,
HAN University of Applied Sciences, Faculty of Health and Social Studies, the Netherlands;
Marieke Kroezen, Catholic University Leuven, Belgium; Jenny Carryer, Massey University
and College of Nurses, New Zealand; Anne-Marie Brady, Trinity College Dublin, Republic of
Ireland; Barbara Todd, Hospital University of Pennsylvania; Kenneth Miller, American
Association of Nurse Practitioners.
b) Competing interests
All authors have completed the ICMJE uniform disclosure form at
www.icmje.org/coi_disclosure.pdf and declare: CB Maier had financial support for the
TaskShift2Nurses Study from the Commonwealth Fund and B. Braun Foundation, through
the Harkness Fellowship. The two funders had no role in the research. The authors did not
have financial relationships with any other organisation that might have an interest in the
submitted work, nor do they possess any other relationships or activities that may have
influenced the submitted work.
c) Funding
This work was supported by The Commonwealth Fund and the B. Braun Foundation, through
the Harkness Fellowship. The views presented here are those of the authors and should not be
attributed to the The Commonwealth Fund or B. Braun Foundation and their directors,
officers, or staff.
d) Data sharing statement
The data on the total number of Nurse Practitioners are available in the manuscript. All other
data (e.g. OECD data) are publicly available.
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References
1. Cometto G, Boerma T, Campbell J, Dare L, Evans T. The Third Global Forum: framing the
health workforce agenda for universal health coverage. Lancet Glob Health. 2013;1(6):e324-5.
2. World Health Organization. A Universal Truth: No Health Without a Workforce. Third Global
Forum on Human Resources for Health Report. Global Health Workforce Alliance and World Health
Organization, 2013 November 2013. Report No.
3. Petterson SM, Liaw WR, Tran C, Bazemore AW. Estimating the residency expansion required
to avoid projected primary care physician shortages by 2035. Ann Fam Med. 2015;13(2):107-14.
4. European Commission. Commission Staff Working Document on an Action Plan for the EU
Health Workforce. SWD(2012) 93 final [Internet]. 2012 February 2015. Available from:
http://ec.europa.eu/health/workforce/docs/staff_working_doc_healthcare_workforce_en.pdf.
5. International Council of Nurses. International Council of Nurses: Definition and characteristics
for nurse practitioner/advanced practice nursing roles Geneva2002 [updated October 2014; cited
2015 July]. Available from: https://acnp.org.au/sites/default/files/33/definition_of_apn-np.pdf.
6. World Health Organization. Task shifting to tackle health worker shortages.
WHO/HSS/200703. 2007.
7. World Health Organization. Task shifting: rational redistribution of tasks among health
workforce teams: global recommendations and guidelines. Geneva: World Health Organization,
2008.
8. Stanik-Hutt J, Newhouse RP, White KM, Johantgen M, Bass EB, Zangaro G, et al. The Quality
and Effectiveness of Care Provided by Nurse Practitioners. The Journal for Nurse Practitioners.
2013;9(8):492-500.e13.
9. Martinez-Gonzalez NA, Tandjung R, Djalali S, Huber-Geismann F, Markun S, Rosemann T.
Effects of physician-nurse substitution on clinical parameters: a systematic review and meta-analysis.
PLoS One. 2014;9(2):e89181.
10. Martinez-Gonzalez NA, Djalali S, Tandjung R, Huber-Geismann F, Markun S, Wensing M, et al.
Substitution of physicians by nurses in primary care: a systematic review and meta-analysis. BMC
Health Serv Res. 2014;14:214.
11. Martinez-Gonzalez NA, Rosemann T, Tandjung R, Djalali S. The effect of physician-nurse
substitution in primary care in chronic diseases: a systematic review. Swiss Med Wkly.
2015;145:w14031.
12. Mundinger MO. Advanced-practice nursing--good medicine for physicians? N Engl J Med.
1994;330(3):211-4.
13. Martin-Misener R, Bryant-Lukosius D, Harbman P, Donald F, Kaasalainen S, Carter N, et al.
Education of advanced practice nurses in Canada. Nurs Leadersh (Tor Ont). 2010;23 Spec No
2010:61-84.
14. Gagan MJ, Boyd M, Wysocki K, Williams DJ. The first decade of nurse practitioners in New
Zealand: A survey of an evolving practice. J Am Assoc Nurse Pract. 2014;26(11):612-9.
15. Ter Maten-Speksnijder A, Grypdonck M, Pool A, Meurs P, van Staa AL. A literature review of
the Dutch debate on the nurse practitioner role: efficiency vs. professional development. Int Nurs
Rev. 2014;61(1):44-54.
16. MacLellan L, Higgins I, Levett-Jones T. Medical acceptance of the nurse practitioner role in
Australia: A decade on. J Am Assoc Nurse Pract. 2014(10):2014 Jun 4.
17. Begley C, Elliott N, Lalor J, Coyne I, Higgins A, Comiskey CM. Differences between clinical
specialist and advanced practitioner clinical practice, leadership, and research roles, responsibilities,
and perceived outcomes (the SCAPE study). J Adv Nurs. 2013;69(6):1323-37.
18. NHS Education for Scotland. Advanced Nursing Practice Toolkit. Current issues in
regulation2012 September 2015. Available from:
http://www.advancedpractice.scot.nhs.uk/regulatory-guidance/current-issues-in-regulation.aspx
19. Chamberlain P, Brown CH, Saldana L. Observational measure of implementation progress in
community based settings: the Stages of Implementation Completion (SIC). Implement Sci.
2011;6:116.
Page 21 of 30
For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml
BMJ Open
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960
on Novem
ber 4, 2020 by guest. Protected by copyright.
http://bmjopen.bm
j.com/
BM
J Open: first published as 10.1136/bm
jopen-2016-011901 on 6 Septem
ber 2016. Dow
nloaded from
For peer review only
22
20. Pulcini J, Jelic M, Gul R, Loke AY. An International Survey on Advanced Practice Nursing
Education, Practice, and Regulation. Journal of Nursing Scholarship. 2010;42(1):31-9.
21. Delamaire M-L, Lafortune G. Nurses in advanced roles: A description and evaluation of
experiences in 12 developed countries. OECD Health Working Paper
2010;54(DELSA/HEA/WD/HWP(2010)5).
22. Heale R, Rieck Buckley C. An international perspective of advanced practice nursing
regulation. Int Nurs Rev. 2015;62(3):421-9.
23. Maier CB. The role of governance in implementing task-shifting from physicians to nurses in
advanced roles in Europe, U.S., Canada, New Zealand and Australia. Health Policy.
2015;119(12):1627-35.
24. Carney M. Regulation of advanced nurse practice: its existence and regulatory dimensions
from an international perspective. J Nurs Manag. 2016;24(1):105-14.
25. Freund T, Everett C, Griffiths P, Hudon C, Naccarella L, Laurant M. Skill mix, roles and
remuneration in the primary care workforce: Who are the healthcare professionals in the primary
care teams across the world? Int J Nurs Stud. 2015;52(3):727-43.
26. Spetz J, Fraher E, Li Y, Bates T. How many nurse practitioners provide primary care? It
depends on how you count them. Med Care Res Rev. 2015;72(3):359-75.
27. Hooker RS, Brock DM, Cook ML. Characteristics of nurse practitioners and physician
assistants in the United States. J Am Assoc Nurse Pract. 2015.
28. Kleinpell R, Goolsby MJ. American Academy of Nurse Practitioners National Nurse
Practitioner Sample Survey: Focus on acute care. Journal of the American Academy of Nurse
Practitioners. 2012;24(12):690-4.
29. Doescher MP, Andrilla CHA, Skillman SM, Morgan P, Kaplan L. The Contribution of Physicians,
Physician Assistants, and Nurse Practitioners Toward Rural Primary Care Findings From a 13-State
Survey. Medical Care. 2014;52(6):549-56.
30. Sangster-Gormley E, Martin-Misener R, Downe-Wamboldt B, Dicenso A. Factors affecting
nurse practitioner role implementation in Canadian practice settings: an integrative review. J Adv
Nurs. 2011;67(6):1178-90.
31. Lowe G, Plummer V, Boyd L. Nurse practitioner roles in Australian healthcare settings.
Nursing Management - UK. 2013;20(2):28-35.
32. Richardson G, Maynard A. Fewer doctors? More nurses? A review of the knowledge base of
doctor-nurse substitution. York: Centre for Health Economics, York Health Economics Consortium,
University of York, 1995 Contract No.: 135.
33. Laurant M, Reeves D, Hermens R, Braspenning J, Grol R, Sibbald B. Substitution of doctors by
nurses in primary care. Cochrane Database of Systematic Reviews. 2005(2).
34. OECD Health Statistics. OECD Health Statistics 2015. Definitions, sources and methods.
Metadata. OECD, 2015 November 2015. Report No.
35. Kaiser Family Foundation. Total Number of Nurse Practitioners, by Gender. State Health
Facts: Kaiser Family Foundation; 2015 [cited 2015 August]. Available from: http://kff.org/other/state-
indicator/total-number-of-nurse-practitioners-by-gender/.
36. American Association of Nurse Practitioners. AANP - about us - historical timeline: American
Association of Nurse Practitioners (AANP); 2015 [cited 2015 December]. Available from:
https://www.aanp.org/about-aanp/historical-timeline.
37. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May 2014. 29-1171
Nurse Practitioners. Bureau of Labor Statistics (BLS), 2014.
38. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May 2012. 29-1171
Nurse Practitioners. Bureau of Labor Statistics (BLS), 2012.
39. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May 2013. 29-1171
Nurse Practitioners. Bureau of Labor Statistics (BLS), 2013.
40. Advisory Committee on Medical Manpower Planning (Capaciteitsorgaan). The 2013
Recommendations for Medical Specialist Training. In the medical, dental, clinical, technological and
mental health areas of training. Utrecht2013 [cited 2015 September]. Available from:
Page 22 of 30
For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml
BMJ Open
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960
on Novem
ber 4, 2020 by guest. Protected by copyright.
http://bmjopen.bm
j.com/
BM
J Open: first published as 10.1136/bm
jopen-2016-011901 on 6 Septem
ber 2016. Dow
nloaded from
For peer review only
23
http://www.capaciteitsorgaan.nl/Portals/0/capaciteitsorgaan/publicaties/Capaciteitsplan%202013/D
EFINITIEF%20hoofdrapport%20engels%20compl.pdf
41. Population Statistics [Internet]. OECD.Stat. 2015 [cited December 2015]. Available from:
http://stats.oecd.org/Index.aspx?DatasetCode=POP_FIVE_HIST.
42. Healthcare Resources: Physicians [Internet]. OECD.Stat. 2015 [cited December 2015].
Available from: http://stats.oecd.org/index.aspx?DataSetCode=HEALTH_STAT.
43. Dutch health professional register (BIG register). Numbers [Cijfers] of health professionals:
Dutch Ministry of Health, Welfare and Sports; 2015 [cited 2015 December]. Available from:
https://www.bigregister.nl/overbigregister/cijfers/.
44. Rowland D. Demographic Methods and Concepts. New York: Oxford University Press; 2003.
45. Reinhardt UE, Hussey PS, Anderson GF. Cross-national comparisons of health systems using
OECD data, 1999. Health Aff (Millwood). 2002;21(3):169-81.
46. Brownson RC, Boehmer TK, Luke DA. Declining rates of physical activity in the United States:
what are the contributors? Annual review of public health. 2005;26:421-43.
47. Anderson GF, Reinhardt UE, Hussey PS, Petrosyan V. It's the prices, stupid: why the United
States is so different from other countries. Health Aff (Millwood). 2003;22(3):89-105.
48. Canadian Institute for Health Information. Regulated Nurses, 2014. Health Workforce
Database: Canadian Institute for Health Information; 2015 [cited 2015 November]. Available from:
https://secure.cihi.ca/estore/productFamily.htm?locale=en&pf=PFC2898&lang=en
49. Nursing and Midwivery Board of Ireland. Statistics. Register statistics 2014 2015 [cited 2015
November]. Available from: http://www.nursingboard.ie/en/statistics.aspx.
50. Nursing and Midwivery Board of Australia. Statistics. 2015 June 2015. Report No.
51. Nursing Council of New Zealand. Annual Report 2015. Wellington, New Zealand: 2015.
52. Dutch Nurse Specialist Registry. Unpublished data on Nurse Specialists (Verpleegkundig
Specialisten), 2009 to 2015, received upon request. 2015.
53. U.S. HRSA National Center for Health Workforce Analysis. Highlights From the 2012 National
Sample Survey of Nurse Practitioners. Rockville, Maryland: U.S. Department of Health and Human
Services, 2014, 2014.
54. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2005. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2005.
55. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2006. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2006.
56. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2007. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2007.
57. Nursing Council of New Zealand. Annual Report 2009. Wellington, New Zealand: 2009.
58. Nursing Council of New Zealand. Annual Report 2010. Wellington, New Zealand: 2010.
59. Nursing Council of New Zealand. Annual Report 2011. Wellington, New Zealand: 2011.
60. Nursing Council of New Zealand. Annual Report 2012. Wellington, New Zealand: 2012.
61. Nursing Council of New Zealand. Annual Report 2013. Wellington, New Zealand: 2013.
62. Nursing Council of New Zealand. Annual Report 2014. Wellington, New Zealand: 2014.
63. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2008. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2008.
64. OECD. OECD Health Statistics 2015. Definitions, Sources and Methods. Professionally active
physicians. OECD, OECD Health Statistics 2015, 2015.
65. OECD. OECD Health Statistics 2015. Definitions, Sources and Methods. Physicians licensed to
practice OECD, OECD Health Statistics 2015, 2015 July 2015. Report No.
66. Spitzer WO, Sackett DL, Sibley JC, Roberts RS, Gent M, Kergin DJ, et al. The Burlington
randomized trial of the nurse practitioner. N Engl J Med. 1974;290(5):251-6.
Page 23 of 30
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67. Record J. Staffing in Primary Care in 1990: Physician replacement and cost savings. New York:
Springer Publishing Company; 1981.
68. Wijers N, van der Burgt R, Laurant M. Verpleegkundig Specialist biedt kansen.
Onderzoeksrapport naar de inzet van de verpleegkundig specialist op de spoedpost in Eindhoven.
[Specialist Nursing offers opportunities. Research report into the use of the specialist nurse at the
emergency station in Eindhoven]. Nijmegen: IQ healthcare, UMC St Radboud; Eindhoven: KOH
Foundation: 2013.
69. Laurant M. Out of hours primary care. International Innovation 2013 [cited 2015 December].
Available from:
http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant
.pdf.
70. DiCenso A, Bryant-Lukosius D, Martin-Misener R, Donald F, Abelson J, Bourgeault I, et al.
Factors enabling advanced practice nursing role integration in Canada. Nurs Leadersh (Tor Ont).
2010;23 Spec No 2010:211-38.
71. Australian Government. Health Legislation Amendment (Midwives and Nurse Practitioners)
Act 2010. No. 29, 2010. C2010A00029. 2010.
72. Scanlon A, Cashin A, Bryce J, Kelly JG, Buckely T. The complexities of defining nurse
practitioner scope of practice in the Australian context. Collegian. 2016;23(1):129-42.
73. Minto R. Barriers on nurse practitioner journey. Nurs N Z. 2008;14(6):4.
74. Begley C, Murphy K, Higgins A, Cooney A. Policy-makers' views on impact of specialist and
advanced practitioner roles in Ireland: the SCAPE study. Journal of Nursing Management.
2014;22(4):410-22.
75. Cashin A. Collaborative arrangements for Australian nurse practitioners: A policy analysis.
Journal of the American Association of Nurse Practitioners. 2014;26(10):550-4.
76. Parliament of New Zealand. Misuse of Drugs Amendment Regulations 2014. 2014/199. 2014.
77. van Meersbergen D. Task-shifting in the Netherlands. World Medical Journal (WMA).
2011;57(4):126-30.
78. Phillips SJ. 27th Annual APRN legislative update: advancements continue for APRN practice.
Nurse Pract. 2015;40(1):16-42.
79. Ono T, Lafortune G, Schoenstein M. Health Workforce Planning in OECD Countries: A Review
of 26 Projection Models from 18 Countries. OECD Health Working Papers [Internet]. 2013 October
2015 [cited 2015 October]; No. 62.
80. American College of Physicians. Nurse Practitioners in Primary Care. Philadelphia: American
College of Physicians, 2009.
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Figure 1 and 2:
Figure 1: Total number of NPs and % of professional nursing workforces, 2015*
Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following secondary data
sources: (Canadian Institute for Health Information 2015, Dutch health professional register (BIG register) 2015,
Dutch Nurse Specialist Registry 2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of
Australia 2015, Nursing and Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015),
Notes: *2015: except for Canada, Ireland: 2014; Data on RNs include NPs, U.S.=United States, NP= Nurse
Practitioner, N=total number, P=Practicing, PA=Professionally Active, R=Registered/Licensed to practice,
RNs=Registered Nurses, Caveats: Netherlands (nurse specialists): an estimated 12 test accounts are in the
database (0.4%) that cannot be filtered out (personal communication, with registry advisor at Verpleegkundig
Specialisten Register, 29 January 2016).
5.6%
1.5%1.3%
0.5%0.3% 0.2%
0.0%
1.0%
2.0%
3.0%
4.0%
5.0%
6.0%
0
20000
40000
60000
80000
100000
120000
140000
160000
180000
200000
U.S.: NP
(N=174,943),
PA
Netherlands:
Nurse specialist
(Verpleegkundig
Specialist)
(N=2,749), R
Canada*: NP
(N= 3,560), P
Australia: NP
(N=1,214), R
New Zealand:
NP (N=142), P
Ireland*:
Advanced NPs
(N=141), PA
Total number of NPs NPs % of all RNs (incl NPs)
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Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*
Sources: Authors’ calculations, based on the following data sources: (U.S. HRSA National Center for Health
Workforce Analysis 2014, Canadian Institute for Health Information 2015, Dutch Nurse Specialist Registry
2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of Australia 2015, Nursing and
Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015), Data on physicians based on OECD
2015 database (OECD Statistics 2015)
Notes: *Year 2013; except for Ireland (2014), United States (2012) depending on years covered by OECD
physician data; NPs= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active,
R=Registered/Licensed to practice, U.S.=United States, Caveats: Netherlands (Nurse specialists): an estimated
12 test accounts are in the database that cannot be filtered out (personal communication, with registry advisor at
Verpleegkundig Specialisten Register, 29 January 2016).
40.5
12.6 9.8 4.4 3.1 3.1
250
416
255
395
270
304
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
400.0
450.0
U.S.: NPs
(N=127,210), P
Netherlands:
Nurse specialists
(N=2,124), R
Canada: NPs (N=
3,477), PA
Australia: NPs
(N=1,004), R
Ireland: Advanced
NPs (N=141), PA
New Zealand: NPs
(N=142), P
NPs per 100,000 population Physicians per 100,000 (OECD 2015)
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References
Canadian Institute for Health Information. (2015). "Regulated Nurses, 2014. Health Workforce
Database." Retrieved November, 2015, from
https://secure.cihi.ca/estore/productFamily.htm?locale=en&pf=PFC2898&lang=en
Dutch health professional register (BIG register). (2015). "Numbers [Cijfers] of health professionals."
Retrieved December, 2015, from https://www.bigregister.nl/overbigregister/cijfers/.
Dutch Nurse Specialist Registry (2015). Unpublished data on Nurse Specialists (Verpleegkundig
Specialisten), 2009 to 2015, received upon request, Dutch Nurse Specialist Registry
(Registratiecommissie Specialismen Verpleegkunde (RSV)).
Kaiser Family Foundation. (2015). "Total Number of Nurse Practitioners, by Gender. State Health
Facts." Retrieved August, 2015, from http://kff.org/other/state-indicator/total-number-of-nurse-
practitioners-by-gender/.
Nursing and Midwivery Board of Australia (2015). Statistics.
Nursing and Midwivery Board of Ireland. (2015). "Statistics. Register statistics 2014." Retrieved
November, 2015, from http://www.nursingboard.ie/en/statistics.aspx.
Nursing Council of New Zealand (2015). Annual Report 2015. Wellington, New Zealand.
OECD Statistics (2015). Healthcare Resources: Physicians. Paris, OECD.Stat.
Page 27 of 30
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on Novem
ber 4, 2020 by guest. Protected by copyright.
http://bmjopen.bm
j.com/
BM
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jopen-2016-011901 on 6 Septem
ber 2016. Dow
nloaded from
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Figure 1 and 2:
Figure 1: Total number of NPs and % of professional nursing workforces, 2015*
Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following data sources:
(Canadian Institute for Health Information 2015, Dutch health professional register (BIG register) 2015, Dutch
Nurse Specialist Registry 2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of Australia
2015, Nursing and Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015),
Notes: *2015: except for Canada, Ireland: 2014; Data on RNs include NPs, U.S.=United States, NP= Nurse
Practitioner, N=total number, P=Practicing, PA=Professionally Active, R=Registered/Licensed to practice,
RNs=Registered Nurses, Caveats: Netherlands (nurse specialists): an estimated 12 test accounts are in the
database (0.4%) that cannot be filtered out (personal communication, with registry advisor at Verpleegkundig
Specialisten Register, 29 January 2016).
5.6%
1.5%1.3%
0.5%0.3% 0.2%
0.0%
1.0%
2.0%
3.0%
4.0%
5.0%
6.0%
0
20000
40000
60000
80000
100000
120000
140000
160000
180000
200000
U.S.: NP
(N=174,943),
PA
Netherlands:
Nurse specialist
(Verpleegkundig
Specialist)
(N=2,749), R
Canada*: NP
(N= 3,560), P
Australia: NP
(N=1,214), R
New Zealand:
NP (N=142), P
Ireland*:
Advanced NPs
(N=141), PA
Total number of NPs NPs % of all RNs (incl NPs)
Page 28 of 30
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Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*
Sources: Authors’ calculations, based on the following data sources: (U.S. HRSA National Center for Health
Workforce Analysis 2014, Canadian Institute for Health Information 2015, Dutch Nurse Specialist Registry
2015, Kaiser Family Foundation 2015, Nursing and Midwivery Board of Australia 2015, Nursing and
Midwivery Board of Ireland 2015, Nursing Council of New Zealand 2015), Data on physicians based on OECD
2015 database (OECD Statistics 2015)
Notes: *Year 2013; except for Ireland (2014), United States (2012) depending on years covered by OECD
physician data; NPs= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active,
R=Registered/Licensed to practice, U.S.=United States, Caveats: Netherlands (Nurse specialists): an estimated
12 test accounts are in the database that cannot be filtered out (personal communication, with registry advisor at
Verpleegkundig Specialisten Register, 29 January 2016).
40.5
12.6 9.8 4.4 3.1 3.1
250
416
255
395
270
304
0.0
50.0
100.0
150.0
200.0
250.0
300.0
350.0
400.0
450.0
U.S.: NPs
(N=127,210), P
Netherlands:
Nurse specialists
(N=2,124), R
Canada: NPs (N=
3,477), PA
Australia: NPs
(N=1,004), R
Ireland: Advanced
NPs (N=141), PA
New Zealand: NPs
(N=142), P
NPs per 100,000 population Physicians per 100,000 (OECD 2015)
Page 29 of 30
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REFERENCES
Canadian Institute for Health Information. (2015). "Regulated Nurses, 2014. Health Workforce
timhttps://secure.cihi.ca/estore/productFamily.htm?locale=en&pf=PFC2898&lang=en
Dutch health professional register (BIG register). (2015). "Numbers [Cijfers] of health professionals."
Retrieved December, 2015, from https://www.bigregister.nl/overbigregister/cijfers/.
Dutch Nurse Specialist Registry (2015). Unpublished data on Nurse Specialists (Verpleegkundig
Specialisten), 2009 to 2015, received upon request, Dutch Nurse Specialist Registry
(Registratiecommissie Specialismen Verpleegkunde (RSV)).
Kaiser Family Foundation. (2015). "Total Number of Nurse Practitioners, by Gender. State Health
Facts." Retrieved August, 2015, from http://kff.org/other/state-indicator/total-number-of-nurse-
practitioners-by-gender/.
Nursing and Midwivery Board of Australia (2015). Statistics.
Nursing and Midwivery Board of Ireland. (2015). "Statistics. Register statistics 2014." Retrieved
November, 2015, from http://www.nursingboard.ie/en/statistics.aspx.
Nursing Council of New Zealand (2015). Annual Report 2015. Wellington, New Zealand.
OECD Statistics (2015). Healthcare Resources: Physicians. Paris, OECD.Stat.
U.S. HRSA National Center for Health Workforce Analysis (2014). Highlights From the 2012 National
Sample Survey of Nurse Practitioners. Rockville, Maryland, U.S. Department of Health and Human
Services, 2014.
Page 30 of 30
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A descriptive, cross-country analysis of the nurse practitioner workforce in six countries: size, growth,
physician substitution potential
Journal: BMJ Open
Manuscript ID bmjopen-2016-011901.R1
Article Type: Research
Date Submitted by the Author: 10-Jul-2016
Complete List of Authors: Maier, Claudia; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing; Technische Universitat Berlin, Department of Healthcare Management
Barnes, Hilary; University of Pennsylvania, Center for Health Outcomes and Policy Research, School of Nursing Aiken, Linda; University of Pennslvania, Center for Health Outcomes and Policy Research, School of Nursing Busse, Reinhard; Technische Universität Berlin, Department of Health Care Management
<b>Primary Subject Heading</b>:
Nursing
Secondary Subject Heading: Global health
Keywords: nursing, health workforce, physicians, PRIMARY CARE, nurse practitioner
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1
A descriptive, cross-country analysis of the nurse practitioner workforce in six
countries: size, growth, physician substitution potential
Corresponding author: Claudia B Maiera) b), MSc
a) Harkness & B. Braun Fellow in Healthcare Policy and Practice
Center for Health Outcomes and Policy Research
University of Pennsylvania, School of Nursing
Claire Fagin Hall
418 Curie Blvd
Philadelphia, PA 19104-4217; b) Department of Healthcare Management,
Technische Universität Berlin, Germany
Administrative office H80
Str. des 17. Juni 135
10623 Berlin, Germany
Phone: +49 176 32944628
Fax: +49 30 314 28433
Hilary Barnes, PhD, CRNP
Postdoctoral Research Fellow
Center for Health Outcomes and Policy Research
University of Pennsylvania
418 Curie Blvd
Claire M. Fagin Hall, 388R
Philadelphia, PA 19104-4217
Phone: +1 215-898-4908
Fax: +1 215-573-2062
Linda H Aiken, PhD, RN
Claire M Fagin Professor and Director
Center for Health Outcomes and Policy Research
University of Pennsylvania
418 Curie Blvd
Claire M. Fagin Hall, 387R
Philadelphia, PA 19104-4217
Phone: +1 215-898-9759
Fax: + 215-573-2062
Reinhard Busse, PhD, MD, MPH, FFPH
Head of the Department of Health Care Management
Faculty of Economics and Management
Head of the Berlin hub of the European Health Observatory on Health Systems and Policies
Technische Universität Berlin
Administrative office H80
Page 1 of 39
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2
Str. des 17. Juni 135
10623 Berlin, Germany
Phone: +49 30 314 28420
Fax: +49 30 314 28433
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ABSTRACT
Objectives. Many countries are facing provider shortages and imbalances in primary care or
are projecting shortfalls for the future, triggered by the rise in chronic diseases and
multimorbidity. In order to assess the potential of Nurse Practitioners (NP) in expanding
access, we analysed the size, annual growth (2005-2015), and the extent of advanced practice
of NPs in six Organisation for Economic Cooperation and Development (OECD) countries.
Design. Cross-country data analysis of national nursing registries, regulatory bodies,
statistical offices data; as well as OECD health workforce and population data, plus literature
scoping review.
Setting/Participants. NP and physician workforces in six OECD countries (Australia,
Canada, Ireland, Netherlands, New Zealand, United States).
Primary and secondary outcome measures. The main outcomes were the absolute and
relative number of NPs per 100,000 population compared to the nursing and physician
workforces; the Compound Annual Growth Rates (CAGR), annual and median percentage
change from 2005-2015; and a synthesis of the literature on the extent of advanced clinical
practice measured by physician substitution effect.
Results. The United States showed the highest absolute number of NPs and rate per
population (40.5 per 100,000 population), followed by the Netherlands and Canada (12.6 and
9.8), Australia (4.4), and Ireland and New Zealand (3.1, respectively). Annual growth rates
were high in all countries, ranging from annual compound rates of 6.1% in the United States
to 27.8% in the Netherlands. Growth rates were between three- and nine-times higher
compared to physicians. Finally, the empirical studies emanating from the literature scoping
reviews suggested that NPs are able to provide 67-93% of all primary care services, yet, based
on limited evidence.
Conclusions. NPs are a rapidly growing workforce with high levels of advanced practice
potential in primary care. Workforce monitoring based on accurate data is critical to inform
educational capacity and workforce planning.
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Strengths and limitations of this study
• This study determines the total and relative size of Nurse Practitioners per 100,000
population and growth rates in comparison to physicians in six OECD countries.
• A strength of this study is the analysis of comprehensive and largely unexplored data
from authoritative sources in the six countries.
• Annual growth rates were calculated for 2005-2015 using compound annual growth
rates (CAGR), annual; and median percentage change to account for excessive yearly
changes found.
• The study faces limitations as to accuracy of data, data variability of the activity levels
of NPs and physicians, yet, for within-country comparisons, we used consistently the
same activity levels for NPs and physicians.
• The few empirical studies on the substitution effect of NPs for physicians show that
NPs can work at high levels of advanced practice, however, future research is
necessary to validate the findings.
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5
BACKGROUND
Health workforce shortages and geographical imbalances exist in many countries worldwide
(1). The need for primary care providers is increasing in response to the intensifying
healthcare needs of their populations, triggered by the increasing rates of patients with chronic
conditions and multimorbidity (2, 3). While educating more physicians is one workforce
strategy, countries are also investing increasingly in a highly qualified nursing workforce,
such as Nurse Practitioners and other Advanced Practice Nurses (NP/APN), with usually
Master’s level education (4). Expanding the roles of nurses combined with task-shifting from
physicians to nurses as suggested by the World Health Organization, has received policy
attention to respond to shortages, long waiting times and high care needs of patients with
chronic conditions (5, 6).
There is a consistent body of evidence showing that nurses with advanced education can
provide high-quality care that is comparable to physicians for a range of acute and chronic
illnesses (7-10). The U.S. was the first country to introduce NPs in 1965 (in Colorado),
followed by Canada in 1967 (in Nova Scotia) (11, 12). NP practice regulations have since
been instituted and managed at the subnational level in these countries. Other countries have
more recently introduced NPs, including the United Kingdom (U.K.), Ireland, the
Netherlands, Australia and New Zealand (13-17).
The extent to which NPs are effective in addressing shortages and the intensifying care needs
of patients with chronic conditions depends on the scale of this workforce, and its integration
and implementation in healthcare (18). Scale in this context refers to two factors, sufficient
numbers of NPs and their extent of advanced practice. Both elements are critical to assess the
contribution of the workforce.
Existing international research on the size of the NP workforce is limited. The international
literature has compared primarily NP education, governance, and regulation of titles (19-23).
In an overview of the primary care workforce in six countries, the total number of NPs was
found to be low in most countries (24). However, the study only provided the total number of
providers, no further information on its relative size compared to other professions or time
trends. A 2010 OECD report found the NP workforce to be the largest in the U.S. in absolute
and relative size compared to the total nursing workforce, followed by Canada, Australia and
Ireland (20). Yet, the report did not differentiate between activity levels and dates back to
2010. It did not provide data on time trends. At the individual country-levels, many studies
exist, particularly in the U.S. that aim to quantify the total number of NPs, by employment,
specialty and clinical practice area (25-28). They found that the various data sources provide a
patchy overview in the U.S., particularly when focusing on the clinically active NPs and
specific specialty areas (25). The comparatively fewer studies analysing the size of NPs in
Canada, Australia, and New Zealand found that the workforce is small, but provided limited
information beyond the number of providers (29, 30).
While NPs perform a substantially expanded range of clinical services, there is limited
knowledge on the detailed level of advanced practice. The 2010 OECD report provides
information on the typical tasks and activities provided by NPs in Australia, Canada, Ireland,
the United Kingdom and the U.S. suggesting that NPs provide a large range of services at the
interface with the medical profession (20). Conceptually, the substitution effect of physicians
by NPs refers to the quantification of how many patients or services in a particular care
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setting can be performed by NPs that are usually provided by physicians (31, 32). In a
systematic review, 30-70% of clinical activities of physicians were found could be taken over
by NPs or other non-physician providers, however, most of the included studies were
conducted in the 1970s and 1980s and included a wide range of non-physician providers,
including NPs, other nursing roles and physician assistants (31). NPs’ roles have expanded
internationally, hence a review focused on NPs only, providing an update of the literature, is
relevant to synthesise the evidence on the extent of advanced practice and variations across
countries.
This study pursued the following three research objectives: 1) to analyse the absolute and
relative size of the NP workforce in six OECD countries (Australia, Canada, Ireland, the
Netherlands, New Zealand, and the U.S.), focusing on practicing NPs, their proportion of the
total nursing workforce and rates per 100,000 population relative to the physician workforce;
2) to examine time trends from 2005-2015 in the NP compared to the physician workforces;
and 3) to synthesise the evidence on the extent of advanced practice in primary care referred
to as physician ‘substitution effect’.
The three objectives are separate, but interrelated: all three parameters (size, growth, percent
of physician substitution) are critical for workforce planning and projections (33). Data on the
three parameters provide the numerical basis in order to forecast the current and future
potential of NPs in addressing the expected growing demand and intensifying healthcare
needs.
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METHODS
Definitions and outcome measures
In order to assess the absolute and relative size of the NP workforce, we followed the OECD
definition of activity levels of health professions: (i) practicing professionals (providing direct
patient care), (ii) professionally active (providing direct patient care, plus working in related
administration, management or research as part of the profession), and (iii) registered/licensed
to practice (authorised to practice, including practicing, professionally active and non-
practicing providers) (34). For this study, the activity status practicing NPs was preferred over
professionally active and registered/licensed, following the OECD (34). In countries with no
available information on the number of practicing NPs, data on professionally active or
registered was used.
To analyse time trends, we compared the yearly growth rates of NPs to physicians from 2005
to 2015 where available. We chose the physician profession as comparator for two reasons.
First, to compare the growth rates to estimate the potential in alleviating shortages and
expanding capacity and second, since OECD data on time trends are of better quality and
comparability than those for the nursing profession.
To analyse the research objective on NPs levels of advanced practice, we performed a
literature scoping review (35), focusing on a concept referred to as ‘substitution effect’, which
estimates the potential of a new, extended professional role in taking up activities of an
established profession (31).
First phase: identification of countries and data availability - the TaskShift2Nurses
Study
We identified countries with NP/APNs based on an expert survey in 39 industrialised
countries (Task-Shift2Nurses Study, 2015). Information on the survey itself, its sampling
strategy, data collection and analysis is provided elsewhere (22, 36). A total of 93 country
experts participated (response rate 85.3%). The survey included questions on scope of
practice and education, data availability, existence of nursing registries, and mandatory vs.
voluntary registration policies, among others. Institutional Review Board (IRB) approval was
obtained at the University of Pennsylvania.
The TaskShift2Nurses study identified eleven countries with NP/APNs: Australia, Canada,
Finland, Ireland, Netherlands, England, Northern Ireland, Scotland, Wales, New Zealand and
the U.S (22, 36). Definitions used were existence of NP/APNs, education at NP/APN level
and advanced practice focusing on primary care, measured by seven clinical activities:
authority to prescribe medications, order medical tests, decide on medical treatment,
diagnose/perform advanced health assessment, referrals, responsibility for a panel of patients,
and first point of contact (4). The survey was integral to this study insofar, as it helped
identify countries with data on NP/APN and the respective authoritative sources.
For the purpose of this study, in a subsequent step we contacted country experts individually
to obtain further information on data sources and holders. Finland and the countries within the
United Kingdom were excluded from this study, because no registry data or other
national/federal or subnational data sources on NP/APNs were identified.
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Second phase: country-specific secondary data collection
In a subsequent step, we retrieved secondary data on NPs for the remaining six countries from
authoritative sources as advised by country experts. All six countries had NP or similar roles
working in advanced practice, of which the titles were regulated and registration was
mandatory. The secondary data collection phase took place between August 2015 and January
2016. These sources included nursing boards or councils (Australia, Ireland, New Zealand),
an institute on health information (Canada), and a nurse specialist registry
(Registratiecommissie Specialismen Verpleegkunde, RSV) in the Netherlands. In the
Netherlands, Nurse Specialists (Verpleegkundig Specialisten) are sometimes referred to as
NPs in English literature (14), however, we decided to keep the translation closest to its
original title, since this title is regulated.
In the U.S., several data sources were reviewed, including data from the Kaiser Family
Foundation (KFF) (37), American Association of Nurse Practitioners (AANP) (38), and the
U.S. Bureau of Labor Statistics (39-41). Challenges of the U.S. data include the co-existence
of multiple sources which calculate the workforce differently. The KFF provided data on
professionally active NPs based on active state NP licenses, however, no data on time trends
were available. The AANP data cover NPs licensed to practice; however, these data are
estimated and actual numbers not available to the public. The U.S. Bureau of Labor Statistics
estimates the professionally active NP workforce, but NP-specific data are only available
since 2012 and exclude self-employed NPs (39-41). To analyse the first research objective,
we chose the data source based on the year of data availability (2015), the completeness of the
data as to the total size of the workforce, and the activity status (data covering ‘practising”
NPs, followed by professionally active and registered/licensed). For the second research
objective, we prioritised on data sources with time series (ideally from 2005 to 2015 or
longest period covered).
Time series data was limited in four countries, the U.S., the Netherlands, Ireland and
Australia. Canada and New Zealand were the only two countries with continuous data on time
series available since 2005, whereas the Netherlands had data since 2009, the year of
introduction of the specialist registry, Ireland since 2010 and Australia since 2012.
Third phase: literature scoping review on the extent of advanced practice
In addition to the secondary data analysis, we conducted a comprehensive literature scoping
review (35), covering Medline, CINAHL, Google Scholar, and grey literature, to identify
studies on substitution effect/extent of advanced practice. Literature scoping reviews have
evolved over the last 20 years as a method for synthesising the evidence on a specific topic or
research question (35, 42). Compared to systematic literature reviews, research questions in
scoping reviews are broader and typically defined per PCC (Population, Concept, Context)
instead of PICO (Participants, Interventions, Comparisons, Outcomes) elements (35), hence,
suitable to a broader research question (see Supplement). Moreover, scoping reviews are
designed to provide a synthesis of a wider and broader type of evidence beyond peer-
reviewed journal articles, and include various, heterogeneous sources instead of focusing on
the best evidence only (43). We followed the methodology by the Joanna Briggs Institute (35)
(see Supplement). Studies were included if they quantified the extent of advanced practice,
also referred to as physician “substitution effect”. We included all evidence that measured
either the percentage of typical physician-provided activities that can be performed by NPs in
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primary care or the percentage of all services that can be provided by NPs (31, 33). Search
terms included various combinations of the terms substitution, nurse practitioner, primary
care, among others (see Supplement). The search was conducted in English, plus we
contacted country experts for additional, grey literature.
Data analysis
Regarding research objective 1, we calculated NP rates per 100,000 population using the
population sizes provided by the OECD 2015 population statistics online database (44). To
compare the density of NPs with physicians, we retrieved the physician ratios per 1,000 from
the OECD database, which we subsequently multiplied by 100 to obtain rates per 100,000
population (45). Data on the nursing workforce was retrieved from the same data holders from
which the data on NPs were obtained, except for the Netherlands where nurse specialists are
registered in a separate registry (46).
As for research objective 2 on time trends, we calculated the yearly percentage change of NPs
and physicians (e.g. 2005-06, 2006-07), covering 2005 to 2015 or years available, to assess
the relative growth of the NP profession compared to the physician profession. Percentage
change is a common arithmetic method, used in many disciplines including demographics
(47). It is based on the calculation of the absolute difference at two points in time and divided
by the original group size, multiplied by 100. This method allows to quantify the increase or
decrease over time periods irrespective of groups’ differences in size. In addition to yearly
percentage changes, we calculated the Compound Annual Growth Rates (CAGR) which is
commonly used in comparison of time trends (48-50), since it smoothes yearly growth rates
over time. In addition, we calculated the average and median percentage change across the
entire time period for each of the country and profession covered (34).
Regarding research objective 3, all studies identified from the literature scoping review were
reviewed according to inclusion and exclusion criteria (see Supplement). Studies were
included if they quantified the extent of substitution effect in primary care, provided the study
was implemented in one of the six countries. We subsequently extracted the numerical results
of the percentage of all services that NPs were able to provide, and information on the study
design, participants, country and service delivery contexts.
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RESULTS
Total and relative size of the Nurse Practitioner workforce
The United States showed the largest number of professionally active NPs (N= 174,943)
compared to the other five OECD countries, which represented 5.6% of its total active U.S.
nursing workforce in 2015 (37) (Figure 1). In the Netherlands and Canada, both the total and
relative size was lower, percentages were 1.5% and 1.3% respectively, based on data on
registered NPs in the Netherlands and practicing NPs in Canada. In Australia, New Zealand
and Ireland, the relative sizes were very small, 0.5% and less.
[Figure 1: Total number of NPs and % of professional nursing workforces, 2015*]
Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following data sources: (37,
46, 51-55),
Notes: *2015: except for Canada, Ireland: 2014; Data on RNs include NPs, U.S.=United States, NP= Nurse
Practitioner, N=total number, P=Practicing, PA=Professionally Active, R=Registered/Licensed to practice,
RNs=Registered Nurses, Caveats: Netherlands (nurse specialists): an estimated 12 test accounts are in the
database (0.4%) that cannot be filtered out (personal communication, with registry advisor at Verpleegkundig
Specialisten Register, 29 January 2016).
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Results regarding the workforce density per population showed similar patterns across the six
countries (Figure 2). The rate of NPs in the United States was highest, at 40.5 practicing NPs
per 100,000 population (44, 56) based on 2012 data to allow for comparisons with physicians.
NPs were less than one fifth of the U.S. physician workforce (44, 45).
In the Netherlands and Canada, rates were considerably lower compared to the U.S. at 12.6
and 9.8 per 100,000 population. Compared to physicians, Australia, Ireland and New Zealand
showed very low rates.
[Figure 2: Nurse Practitioner density compared to physicians per 100,000 population, 2013*]
Sources: Authors’ calculations, based on the following data sources: (37, 51-56), Data on physicians based on
the OECD 2015 database (45), drawn from the following primary data sources: United States: American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia:
Australian Institute of Health and Welfare (AIHW), New Zealand: Medical Council Medical Register (57, 58).
Notes: *Year 2013; except for Ireland (2014), United States (2012) depending on years covered by OECD
physician data; NPs= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active,
R=Registered/Licensed to practice, U.S.=United States, Caveats: Netherlands (Nurse specialists): an estimated
12 test accounts are in the database that cannot be filtered out (personal communication, with registry advisor at
Verpleegkundig Specialisten Register, 29 January 2016).
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Growth of the Nurse Practitioner workforce from 2005-2015
All countries showed a continuous growth of their NP workforce from 2005 to 2015 or those
years available (Table 1). However, growth rates varied considerably across countries; and
within countries between NPs and physicians.
In the U.S., NPs licensed to practice increased from an estimated 106,000 in 2004 to 192,000
in 2014 (38). Rates per 100,000 population increased from 35.87 to 60.22 NPs per 100,000
population. Data on professionally active NPs showed an increase from 105,780 to 122,050
NPs, yet were only available from 2012 to 2014 (39-41).
In the Netherlands, the numbers of Nurse Specialists registered increased rapidly, from 140 in
2009 to 2,749 in 2015. The rate of Nurse Specialists per 100,000 population in the
Netherlands showed the most rapid increase of all countries studied, more than 14-fold, from
0.85 Nurse Specialists in 2009 to 14.74 Nurse Specialists per 100,000 in 2014.
In Canada, the rate of NPs per 100,000 increased from 2.9 in 2005 to 10.7 in 2014, more than
three-fold. In Australia, the NP rate grew from 3.5 in 2012 to 5 per 100,000 population in
2014. Although a rapid increase took place in New Zealand from 0.3 in 2005 to 3.1 in 2014,
and in Ireland from 0.8 in 2010 to 3.1 in 2014, total numbers remained at low levels.
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Nurse Practitioner compared to physician growth rates
We present compound annual growth rates (CAGR), and the median percentage changes over
the 2005-2015 period to show differences in the calculation methods (table 2). In order to
account for the extremly high growth rates in the first year in the Netherlands and Ireland due
to the small numbers (Netherlands: 2009-10, Ireland: 2010-11), we calculated the CAGR for
the full period and the CAGR without the first year for the two countries.
Growth among NPs was high in all countries, and consistently and considerably higher than
among physicians. The compound growth rate among Nurse Specialists in the Netherlands
was 27.8% (CAGR 2010-2015), the highest of all six countries. The yearly growth was higher
than that of its medical workforce at 2.9%, overall yearly growth was more than 9-times
higher. In New Zealand and Canada, compound annual growth of NPs was 27.3% and 16.7%
respectively, approximately nine- and five-times higher than that of their medical workforces
(2.8%, and 3.3%). Ireland showed a comparatively lower yearly increase of its NP workforce,
yet, still a more than four-times growth compared to its physician workforce. Of the six
countries, the United States had the lowest annual compound growth of 6.1% or 7.4%
annually depending on the data sources, yet, was still more than three-times higher than that
of physicians (38-41, 44, 45).
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Table 1: Total number of Nurse Practitioners and Physicians, six countries, 2005-2015 (or years available)
Sources: authors’ calculations, based on the following data sources (38-41, 45, 51-55, 59-68), The OECD statistics on physicians are based on the following primary data sources: United States:
American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia: Australian Institute of Health and Welfare (AIHW),
New Zealand: Medical Council Medical Register (57, 58).
Notes: NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats: United States: *data on
professionally active Nurse Practitioners do not include self-employed, hence underestimate totals (39), ^year 2004 (in lieu of 2005 data availability) e= data on registered NPs are estimates, exact
numbers are not publicly available (38), Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot
be filtered out (estimated 8 cases yearly in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January
2016), Canada: OECD data on MDs, based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010, due to change of data holders. (57, 58)
Year United States Canada Netherlands Australia New Zealand Ireland
NP NP MD NP MD NS MD NP MD NP MD NP MD
PA R R PA PA R R R R R R PA PA
2005 .. 106,000e^ 902,053 943 69,619 .. 55,673 .. 67,890 14 11,555 .. ..
2006 .. .. 921,904 1,129 70,870 .. 57,098 .. 71,740 21 11,889 .. 11,617
2007 .. 120,000e 941,304 1,344 72,903 .. 58,661 .. 77,193 30 12,318 .. 12,311
2008 .. .. 954,224 1,626 75,155 .. 60,300 .. 78,909 46 12,746 .. 13,022
2009 .. 130,000e 972,376 1,990 78,623 140 62,057 .. 82,895 50 13,176 .. 13,663
2010 .. 140,000e 985,375 2,486 80,895 807 63,585 .. .. 72 13,398 38 14,029
2011 .. 148,000e 1,004,635 2,777 84,313 1,272 65,568 .. 87,790 91 14,021 97 14,814
2012 105,780* 157,000e 1,026,788 3,157 87,306 1,847 68,119 788 91,504 103 14,280 109 14,498
2013 113,370* 171,000e 1,045,910 3,477 90,205 2,124 69,942 1,004 91,467 117 14,596 123 14,054
2014 122,050* 192,000e .. 3,786 .. 2,480 .. 1,165 .. 138 14,787 141 14,016
2015 .. .. .. .. .. 2,749 .. 1,214 .. 157 .. .. ..
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Table 2: Annual growth of the nurse practitioner and physician workforces, measured by yearly percentage change (%), median percentage change
and Compound Annual Growth Rate (CAGR, %), in six countries, 2005-2015 (or years available)
Sources: authors’ calculations, based on the following data sources (38-41, 45, 51-55, 59-68). The OECD statistics on physicians are based on the following primary data sources: United States: American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia: Australian Institute of Health and Welfare (AIHW),
New Zealand: Medical Council Medical Register (57, 58).
Notes: CAGR=Compound Annual Growth Rate, [1]=CAGR (2004/2014) calculated based on 2004-2014 data (2004 data used in lieu of missing 2005 data) [2]=CAGR (2010-2015), 2009-10 was
excluded due to excessive growth rate caused by small numbers (CAGR 2009-2015: 64.3%, not shown), [3]=CAGR (2011-2014), 2010-11 data excluded (CAGR 2010-14: 38.8%, not shown),
PC=Percentage Change, NP=Nurse Practitioners, NS=Nurse Specialists, MD=Medical Doctors/Physicians, P=Practicing, PA=Professionally Active, R=Registered, ..= not available, Caveats:
United States: *data on professionally active Nurse Practitioners do not include self-employed (39). °Data on registered NPs are estimates, exact numbers are not publicly available (38),
Netherlands: Data on nurse specialists (NS, R) include approximately 10 invalid cases per year used as test accounts (range 8-12) in the database that cannot be filtered out (estimated 8 cases yearly
in 2009/2010/2011/2012 and 12 in 2013/2014/2015) (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January 2016), Canada: OECD data on MDs,
based on two combined data sources, which may overstate the number of physicians, since interns and residents may be registered twice, Australia: break in OECD time series data on MDs in 2010,
due to change of data holders. (57, 58)
Year United States Canada Netherlands Australia New Zealand Ireland
NP NP MD NP MD NS MD NP MD NP MD NP MD
PA* R° R PA PA R R R R R R PA PA
2005-2006 .. ..^ 2.2% 19.7% 1.8% .. 2.6% .. 5.7% 50.0% 2.9% .. ..
2006-2007 .. .. 2.1% 19.0% 2.9% .. 2.7% .. 7.6% 42.9% 3.6% .. 6.0%
2007-2008 .. ..^ 1.4% 21.0% 3.1% .. 2.8% .. 2.2% 53.3% 3.5% .. 5.8%
2008-2009 .. .. 1.9% 22.4% 4.6% .. 2.9% .. 5.1% 8.7% 3.4% .. 4.9%
2009-2010 .. 7.7% 1.3% 24.9% 2.9% 476.4% 2.5% .. .. 44.0% 1.7% .. 2.7%
2010-2011 .. 5.7% 2.0% 11.7% 4.2% 57.6% 3.1% .. .. 26.4% 4.6% 155.3% 5.6%
2011-2012 .. 6.1% 2.2% 13.7% 3.5% 45.2% 3.9% .. 4.2% 13.2% 1.8% 12.4% -2.1%
2012-2013 7.2% 8.9% 1.9% 10.1% 3.3% 15.0% 2.7% 27.4% 0% 13.6% 2.2% 12.8% -3.1%
2013-2014 7.7% 12.3 .. 8.9% .. 16.8% .. 16.0% .. 17.9% 1.3% 14.6% -0.3%
2014-2015 .. .. .. .. .. 10.9% .. 4.2% .. 13.8% .. .. ..
Median PC 7.5% 7.7% 2% 19.0% 3.2% 30.1% 2.8% 16.0% 4.6% 22.2% 2.9% 13.7% 3.8%
CAGR 7.4% 6.1%[1] 1.9% 16.7% 3.3% 27.8%[2] 2.9% 15.5% 3.8% 27.3% 2.8% 13.3%[3] 2.4%
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Extent of advanced clinical practice
The scoping review yielded a total of 1,022 results. After removal of 31 duplicates, the titles
of 991 records were screened and the full-text of 46 studies analysed according to the
inclusion/exclusion criteria (see Supplement for additional information). The review resulted
in five results, together reporting the findings from three empirical studies, quantifying the
extent of clinical practice of NPs compared to physicians in primary care. These were
conducted in the U.S., Canada and the Netherlands (Table 3). No studies conducted in the
three other countries were identified. The five studies found NPs able to provide between 67%
and 93% of primary care services, emanating from one Randomised Controlled Trial (RCT)
conducted in Canada (69), one quasi-experimental study in the Netherlands (70-72), and one
survey to physicians and NPs in the U.S. (28) (see Supplement). The findings were based on
small sample sizes, did not differentiate between specialty areas of NPs, covered different
practice areas within primary care, such as rural areas in the U.S. (28) or out-of-hours services
in the Netherlands. Moreover, the RCT in Canada was conducted more than 40 years ago
(69).
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Table 3: Level of advanced clinical practice, measured by physician “substitution effect” of nurse practitioners
Country Study design
(Years) Setting Participants Results Referen
ce
Canada RCT to assess the
effects of substituting NPs
for physicians in
primary care (1971-1972).
Two suburban
Ontario family practices
Total patient N = 1,598
families (4,325 individuals) of which 529
families (1,398
individuals) were randomized to each
physician; 270 families
(765 individuals) were
randomized to each NP
67% of all primary care patient visits can be provided by NPs.
Care delivery was similar between physicians and NPs. There were no
statistically significant differences between patients seen by NPs compared
to patients seen by physicians in patient functional capacity, indexes of social and emotional function, mortality, or satisfaction with care.
(69)
Netherlands Quasi-experimental
study to compare the number of
patients and
caseloads between NPs and GPs in
out-of-hours
services (2011 to 2012)
Out-of-hours
primary care
Intervention: one NP and
four GPs, control: five GPs working in out-of-
hours services. Total
patient N=12,092 from one GP cooperative
extracted from medical
records
More than 77% of patients fit the scope-of-practice of Nurse Practitioners
(Verpleegkundig Specialist) in out-of-hours care. On average 16.3% of all patients were treated by NPs, whereas 20.9% of
patients were treated by GPs.
75-83% of clinical activities in out-of-hours primary care settings (weekend
shifts in GP practices) could be taken over by Nurse Specialists
(Verpleegkundig Specialist)
(70)
(71, 72)
U.S. Self-report, mailed survey to a random
sample of 4,000
physicians and
3,000 NPs with
rural addresses (all
specialties)
Rural primary care in 13
states with at
least 2 from
each U.S.
Census
Region (4
regions).
Final sample included
788 primary care
physicians (response
rate: 25%); and 918
primary care NPs (40%)
75-93% of weekly primary care outpatient visits can be provided by NPs.a
In the outpatient setting, primary care clinical activitiesb were comparable
between physicians and NPs in the outpatient setting.
(28)
Source: see directly in the table, see Supplement for more details
Notes: NP = nurse practitioners; RCT = randomised controlled trial; GP = general practitioner a In an unadjusted regression model, NP average weekly number of outpatient visits was 75% of physician volume. In an adjusted model (age, sex, geographic location, and
practice setting), NP average weekly number of outpatient visits was 93% of physician volume. b On average, physicians conducted more well-child visits than NPs (12.6 vs. 7.4, p <0.001). Differences for prenatal visits and minor procedures were non-significant.
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DISCUSSION
The size of the NP workforce in the six countries studied is variable, but growing rapidly,
with high levels of practice in primary care, yet based on limited evidence. The U.S. is the
only country where the NP workforce has reached a considerable density of approximately
40.5 practicing NPs per 100,000 population, in other countries the workforce is smaller,
ranging from 12.6 per 100,000 population in the Netherlands to low levels in New Zealand
and Ireland. Yet, the workforce has rapidly and consistently grown since 2005 in all countries,
at much higher rates than the physician workforce. Moreover, the few existing empirical
studies show the potentially large and wide range of advanced clinical activities that NPs can
provide. The studies suggest that between 67 and 93% of primary care visits and services can
be safely provided by NPs. Taken together, the findings indicate that the NP workforce holds
future promise in filling unmet care needs in primary care.
The study faces several limitations. First, data sources varied in the activity levels covered,
e.g. practicing, professionally active or registered NPs and physicians across countries. This
limitation is faced by all international data on health workforces, including the OECD and
WHO, since countries use different registration policies and data collection methodologies.
However, for within-country comparisons, we consistently compared the same activity levels
of NPs and physicians. Second, we took the OECD data on physicians at face value; however,
among the underlying primary data sources, differences may exist in terms of accuracy and
validity. Future research could compare the accuracy of the OECD data with individual
national/subnational primary data sources. Third, due to the U.S. decentralised approach of
licensing NPs, several different data sources and holders were identified. Large differences
exist across data sources in terms of size, and activity levels, limiting overall quality of data.
Additionally, state-level authority over NP licensing may lead to double counting NPs who
hold licenses in multiple states. Moreover, data on time trends of ten years were based on
estimates and covered the licensed workforce. Hence, the U.S. data can at best be
approximations to the actual number of practicing NPs over the ten-year period and therefore
need to be interpreted in light of the limitations.
Our results are largely in line with previous international research showing the relatively
small scale of the NP workforce (20, 24). Reasons for the differences between the scale of the
NP workforce in the U.S. and other countries have not been empirically validated. It is
assumed they may be multifactorial. Not only the years of existence may play a role, as the
U.S. was the first country to implement NPs in 1965 (in the earliest adopting state), but other
factors may also influence their size and growth. Canada (Nova Scotia) introduced the first
NPs only two years later, but relies on a much lower total number and density of NPs than the
U.S.. Reasons for a small NP base in Canada have been discussed, and include limited role
clarity, differences across provinces and territories in education and uptake, and challenges in
creating positions for NPs (12, 29, 73). Moreover, large variations in the NP density exist
across provinces and territories, rural versus urban areas and by employer, suggesting a more
granular analysis of potentially influencing policies and other factors may be needed (51). The
low numbers in the Netherlands, Australia, and particularly in New Zealand and Ireland are at
least partly influenced by the fact that NPs were introduced much later in these countries
(1990s and 2000s) than in the U.S. and Canada (13, 24, 61, 74-76).
Time series data showed a considerable increase of NPs in all countries studied, much higher
yearly growth than found in the medical workforces. This trend may partially but not entirely
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be related to the fact that increases in very small numbers result in large growth rates. We
took account of this by excluding extreme values from the CAGR calculations for Ireland and
the Netherlands, and calculated median percentage changes which were comparable to
CAGR.
The continuous and higher growth rates point to an emerging NP workforce that may not have
reached its full numerical potential, as compared to professions with a longer tradition, such
as the physician workforce. Many countries in our study have removed or eased regulatory
barriers to expanded NP scope of practice, such as Australia, Canada, New Zealand, the
Netherlands and the U.S. (77-81). Canada and New Zealand expanded prescriptive authority
for NPs in 2012 and 2014, respectively (78, 82). In Australia, NPs got access to the Medical
and Pharmaceutical Benefits Scheme in 2010, easing their practice, the Netherlands has
regulated the Nurse Specialist profession in 2009 and expanded scope of practice in 2011,
entering into effect in 2012 (79, 83). In the U.S., an increasing number of states have removed
regulatory barriers by revising scope of practice laws over the last decade (80, 84) . Future
research is warranted to identify systemic facilitators and barriers that may cause variations in
the implementation of NP roles in different country contexts.
Moreover, medical student intake or residency places are restricted by some sort of quota
system or numerus clausus in all countries, to avoid an excessive medical workforce and at
the same time, physician shortages (85). These regulatory measures may explain the moderate
annual increase among the medical workforce. To which extent countries’ workforce planning
take account of NPs or other APNs to project student intake, has received little attention in
research and practice. Future research on workforce planning should include NPs in relation
to physician growth and the potential for substitution, such as estimating the number of
“physician-equivalent NPs” as a strategy to ease future projected workforce shortages. In the
Netherlands, for instance, Nurse Specialists have been added to its physician workforce
projection as one scenario to account for substitution (33). Yet, reasons for cross-country
variations in health workforce supply, skill-mix changes across high-income countries and
access to care is one area of research that warrant further high-quality evaluations.
The findings from our literature scoping review show that NPs could cover a range of
approximately 67 to 93% of all primary care services. Findings are largely in line with a
report by the American College of Physicians, suggesting that 60-90% of primary care can be
provided by NPs (86). A previous review showed a lower range of 30% to 70% of physician-
provided activities that could be taken over by NPs, yet comparability is limited, since the
review covered NPs and other non-physician providers (31). Yet, the number of empirical
studies we identified is small, does not take into account variations in specialty areas, is
based on small sample sizes and was conducted in different provider contexts. Hence the
findings require cautious interpretation of the data and call for more research in the field.
This study shows a rapid yearly increase of the NP workforce, which suggests more attention
should be paid to the monitoring of this workforce in the future to expand capacity and access
to healthcare services. To date, data on the NP workforce is not covered in international health
workforce databases, such as the WHO, OECD, or international nursing bodies and
associations. Most data is publicly available or available upon request from the respective
nursing regulatory bodies’ websites or other data holders. In the U.S. with the numerically
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largest workforce, data availability is limited, a barrier for the monitoring of the workforce.
Integrating NPs in health workforce data and intelligence systems at national and international
level is therefore critical for their development, education and monitoring.
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CONCLUSIONS
Nurse Practitioners are a rapidly growing workforce internationally, growing faster than the
medical profession in the six countries studied. Data on the size and growth of NPs are
available in all six countries, however, with variations in quality and completeness,
particularly on time trends. Information on the extent of potential physician substitution effect
is limited, yet, critical for workforce planning. As this workforce grows, improving data
availability and monitoring as part of the overall health workforce is critical to inform
educational capacity, uptake in practice and workforce planning.
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a) Contributorship statement
CBM had the main role in the study design, data collection, and analysis, and wrote the
manuscript. HB contributed to the identification of U.S. data and the literature review, and
was involved in the revisions of the manuscript. LHA and RB gave overall guidance on the
study, the methodology, and reviewed the paper. All authors read, commented upon, and
approved the final manuscript.
Acknowledgements: We are grateful to the Dutch Registration Commission for Nurse
Specialists in the Netherlands (Registratiecommissie Specialismen Verpleegkunde, RSV) for
their support in providing time series data and important additional contextual information.
Moreover, we thank the 93 country experts who participated in the survey. In particular, we
thank the following country experts for providing additional information on data sources:
Julianne Bryce, Australian Nursing and Midwifery Federation; Miranda Laurant, HAN
University of Applied Sciences, Faculty of Health and Social Studies, the Netherlands;
Marieke Kroezen, Catholic University Leuven, Belgium; Jenny Carryer, Massey University
and College of Nurses, New Zealand; Anne-Marie Brady, Trinity College Dublin, Republic of
Ireland; Barbara Todd, Hospital University of Pennsylvania; Kenneth Miller, American
Association of Nurse Practitioners.
b) Competing interests
All authors have completed the ICMJE uniform disclosure form at
www.icmje.org/coi_disclosure.pdf and declare: CB Maier had financial support for the
TaskShift2Nurses Study from the Commonwealth Fund and B. Braun Foundation, through
the Harkness Fellowship, LH Aiken received funding from the National Institutes of Health
(NIH), National Institute of Nursing Research. The funders had no role in the research. The
authors did not have financial relationships with any other organisation that might have an
interest in the submitted work, nor do they possess any other relationships or activities that
may have influenced the submitted work.
c) Funding
This work was supported by The Commonwealth Fund and the B. Braun Foundation, through
the Harkness Fellowship (Maier), and the National Institutes of Health, National Institute of
Nursing Research (Grant No. T32NR007104, Aiken, PI). The views presented here are those
of the authors and should not be attributed to the funders who had no role in the study.
d) Data sharing statement
The data on the total number of Nurse Practitioners are available in the manuscript. All other
data (e.g. OECD data) are publicly available.
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References
1. Cometto G, Boerma T, Campbell J, Dare L, Evans T. The Third Global Forum: framing the
health workforce agenda for universal health coverage. Lancet Glob Health. 2013;1(6):e324-5.
2. World Health Organization. A Universal Truth: No Health Without a Workforce. Third Global
Forum on Human Resources for Health Report. Global Health Workforce Alliance and World Health
Organization, 2013 November 2013. Report No.: Forum Report, Third Global Forum on Human
Resources for Health.
3. OECD. Health Workforce Policies in OECD Countries: Right Jobs, Right Skills, Right Places.
Paris: 2016.
4. International Council of Nurses. International Council of Nurses: Definition and characteristics
for nurse practitioner/advanced practice nursing roles Geneva2002 [updated October 2014; cited
2016 April]. Available from: https://acnp.org.au/sites/default/files/33/definition_of_apn-np.pdf.
5. World Health Organization. Task shifting to tackle health worker shortages.
WHO/HSS/200703. 2007.
6. World Health Organization. Task shifting: rational redistribution of tasks among health
workforce teams: global recommendations and guidelines. Geneva: World Health Organization,
2008.
7. Stanik-Hutt J, Newhouse RP, White KM, Johantgen M, Bass EB, Zangaro G, et al. The Quality
and Effectiveness of Care Provided by Nurse Practitioners. The Journal for Nurse Practitioners.
2013;9(8):492-500.e13.
8. Martinez-Gonzalez NA, Tandjung R, Djalali S, Huber-Geismann F, Markun S, Rosemann T.
Effects of physician-nurse substitution on clinical parameters: a systematic review and meta-analysis.
PLoS One. 2014;9(2):e89181.
9. Martinez-Gonzalez NA, Djalali S, Tandjung R, Huber-Geismann F, Markun S, Wensing M, et al.
Substitution of physicians by nurses in primary care: a systematic review and meta-analysis. BMC
Health Serv Res. 2014;14:214.
10. Martinez-Gonzalez NA, Rosemann T, Tandjung R, Djalali S. The effect of physician-nurse
substitution in primary care in chronic diseases: a systematic review. Swiss Med Wkly.
2015;145:w14031.
11. Mundinger MO. Advanced-practice nursing--good medicine for physicians? N Engl J Med.
1994;330(3):211-4.
12. Martin-Misener R, Bryant-Lukosius D, Harbman P, Donald F, Kaasalainen S, Carter N, et al.
Education of advanced practice nurses in Canada. Nurs Leadersh (Tor Ont). 2010;23 Spec No
2010:61-84.
13. Gagan MJ, Boyd M, Wysocki K, Williams DJ. The first decade of nurse practitioners in New
Zealand: A survey of an evolving practice. J Am Assoc Nurse Pract. 2014;26(11):612-9.
14. Ter Maten-Speksnijder A, Grypdonck M, Pool A, Meurs P, van Staa AL. A literature review of
the Dutch debate on the nurse practitioner role: efficiency vs. professional development. Int Nurs
Rev. 2014;61(1):44-54.
15. MacLellan L, Higgins I, Levett-Jones T. Medical acceptance of the nurse practitioner role in
Australia: A decade on. J Am Assoc Nurse Pract. 2014(10):2014 Jun 4.
16. Begley C, Elliott N, Lalor J, Coyne I, Higgins A, Comiskey CM. Differences between clinical
specialist and advanced practitioner clinical practice, leadership, and research roles, responsibilities,
and perceived outcomes (the SCAPE study). J Adv Nurs. 2013;69(6):1323-37.
17. NHS Education for Scotland. Advanced Nursing Practice Toolkit. Current issues in
regulation2012 September 2015. Available from:
http://www.advancedpractice.scot.nhs.uk/regulatory-guidance/current-issues-in-regulation.aspx
18. Chamberlain P, Brown CH, Saldana L. Observational measure of implementation progress in
community based settings: the Stages of Implementation Completion (SIC). Implement Sci.
2011;6:116.
19. Pulcini J, Jelic M, Gul R, Loke AY. An International Survey on Advanced Practice Nursing
Education, Practice, and Regulation. Journal of Nursing Scholarship. 2010;42(1):31-9.
Page 23 of 39
For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml
BMJ Open
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960
on Novem
ber 4, 2020 by guest. Protected by copyright.
http://bmjopen.bm
j.com/
BM
J Open: first published as 10.1136/bm
jopen-2016-011901 on 6 Septem
ber 2016. Dow
nloaded from
For peer review only
24
20. Delamaire M-L, Lafortune G. Nurses in advanced roles: A description and evaluation of
experiences in 12 developed countries. OECD Health Working Paper 2010;54 (DELSA/HEA/WD/HWP
(2010)5).
21. Heale R, Rieck Buckley C. An international perspective of advanced practice nursing
regulation. Int Nurs Rev. 2015;62(3):421-9.
22. Maier CB. The role of governance in implementing task-shifting from physicians to nurses in
advanced roles in Europe, U.S., Canada, New Zealand and Australia. Health Policy.
2015;119(12):1627-35.
23. Carney M. Regulation of advanced nurse practice: its existence and regulatory dimensions
from an international perspective. J Nurs Manag. 2016;24(1):105-14.
24. Freund T, Everett C, Griffiths P, Hudon C, Naccarella L, Laurant M. Skill mix, roles and
remuneration in the primary care workforce: Who are the healthcare professionals in the primary
care teams across the world? Int J Nurs Stud. 2015;52(3):727-43.
25. Spetz J, Fraher E, Li Y, Bates T. How many nurse practitioners provide primary care? It
depends on how you count them. Med Care Res Rev. 2015;72(3):359-75.
26. Hooker RS, Brock DM, Cook ML. Characteristics of nurse practitioners and physician
assistants in the United States. J Am Assoc Nurse Pract. 2015.
27. Kleinpell R, Goolsby MJ. American Academy of Nurse Practitioners National Nurse
Practitioner Sample Survey: Focus on acute care. Journal of the American Academy of Nurse
Practitioners. 2012;24(12):690-4.
28. Doescher MP, Andrilla CHA, Skillman SM, Morgan P, Kaplan L. The Contribution of Physicians,
Physician Assistants, and Nurse Practitioners Toward Rural Primary Care Findings From a 13-State
Survey. Medical Care. 2014;52(6):549-56.
29. Sangster-Gormley E, Martin-Misener R, Downe-Wamboldt B, Dicenso A. Factors affecting
nurse practitioner role implementation in Canadian practice settings: an integrative review. J Adv
Nurs. 2011;67(6):1178-90.
30. Lowe G, Plummer V, Boyd L. Nurse practitioner roles in Australian healthcare settings.
Nursing Management - UK. 2013;20(2):28-35.
31. Richardson G, Maynard A. Fewer doctors? More nurses? A review of the knowledge base of
doctor-nurse substitution. York: Centre for Health Economics, York Health Economics Consortium,
University of York, 1995 Contract No.: 135.
32. Laurant M, Reeves D, Hermens R, Braspenning J, Grol R, Sibbald B. Substitution of doctors by
nurses in primary care. Cochrane Database of Systematic Reviews. 2005(2).
33. Advisory Committee on Medical Manpower Planning (Capaciteitsorgaan). The 2013
Recommendations for Medical Specialist Training. In the medical, dental, clinical, technological and
mental health areas of training. Utrecht2013 [cited 2015 September]. Available from:
http://www.capaciteitsorgaan.nl/Portals/0/capaciteitsorgaan/publicaties/Capaciteitsplan%202013/D
EFINITIEF%20hoofdrapport%20engels%20compl.pdf
34. OECD Health Statistics. OECD Health Statistics 2015. Definitions, sources and methods.
Metadata. OECD, 2015 November 2015. Report No.
35. The Joanna Briggs Institute. The Joanna Briggs Institute Reviewers’ Manual 2015.
Methodology for JBI Scoping Reviews. The Joanna Briggs Institute (JBI), 2015.
36. Maier CB, Aiken LH. Task-shifting from physicians to nurses in primary care in 39 countries: a
cross-country comparative study. European Journal of Public Health. In press.
37. Kaiser Family Foundation. Total Number of Nurse Practitioners, by Gender. State Health
Facts: Kaiser Family Foundation; 2015 [cited 2015 August]. Available from: http://kff.org/other/state-
indicator/total-number-of-nurse-practitioners-by-gender/.
38. American Association of Nurse Practitioners. AANP - about us - historical timeline: American
Association of Nurse Practitioners (AANP); 2015 [cited 2015 December]. Available from:
https://www.aanp.org/about-aanp/historical-timeline.
39. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May 2014. 29-1171
Nurse Practitioners. Bureau of Labor Statistics (BLS), 2014.
Page 24 of 39
For peer review only - http://bmjopen.bmj.com/site/about/guidelines.xhtml
BMJ Open
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960
on Novem
ber 4, 2020 by guest. Protected by copyright.
http://bmjopen.bm
j.com/
BM
J Open: first published as 10.1136/bm
jopen-2016-011901 on 6 Septem
ber 2016. Dow
nloaded from
For peer review only
25
40. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May 2012. 29-1171
Nurse Practitioners. Bureau of Labor Statistics (BLS), 2012.
41. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May 2013. 29-1171
Nurse Practitioners. Bureau of Labor Statistics (BLS), 2013.
42. Armstrong R, Hall BJ, Doyle J, Waters E. Cochrane Update. 'Scoping the scope' of a cochrane
review. Journal of public health (Oxford, England). 2011;33(1):147-50.
43. Cacchione PZ. The Evolving Methodology of Scoping Reviews. Clinical nursing research.
2016;25(2):115-9.
44. Population Statistics [Internet]. OECD.Stat. 2015 [cited December 2015]. Available from:
http://stats.oecd.org/Index.aspx?DatasetCode=POP_FIVE_HIST.
45. Healthcare Resources: Physicians [Internet]. OECD.Stat. 2015 [cited December 2015].
Available from: http://stats.oecd.org/index.aspx?DataSetCode=HEALTH_STAT.
46. Dutch health professional register (BIG register). Numbers [Cijfers] of health professionals:
Dutch Ministry of Health, Welfare and Sports; 2015 [cited 2015 December]. Available from:
https://www.bigregister.nl/overbigregister/cijfers/.
47. Rowland D. Demographic Methods and Concepts. New York: Oxford University Press; 2003.
48. Reinhardt UE, Hussey PS, Anderson GF. Cross-national comparisons of health systems using
OECD data, 1999. Health Aff (Millwood). 2002;21(3):169-81.
49. Brownson RC, Boehmer TK, Luke DA. Declining rates of physical activity in the United States:
what are the contributors? Annual review of public health. 2005;26:421-43.
50. Anderson GF, Reinhardt UE, Hussey PS, Petrosyan V. It's the prices, stupid: why the United
States is so different from other countries. Health Aff (Millwood). 2003;22(3):89-105.
51. Canadian Institute for Health Information. Regulated Nurses, 2014. Health Workforce
Database: Canadian Institute for Health Information; 2015 [cited 2015 November]. Available from:
https://secure.cihi.ca/estore/productFamily.htm?locale=en&pf=PFC2898&lang=en
52. Nursing and Midwifery Board of Ireland. Statistics. Register statistics 2014 2015 [cited 2015
November]. Available from: http://www.nursingboard.ie/en/statistics.aspx.
53. Nursing and Midwifery Board of Australia. Statistics. 2015 June 2015. Report No.
54. Nursing Council of New Zealand. Annual Report 2015. Wellington, New Zealand: 2015.
55. Dutch Nurse Specialist Registry. Unpublished data on Nurse Specialists (Verpleegkundig
Specialisten), 2009 to 2015, received upon request. 2015.
56. U.S. HRSA National Center for Health Workforce Analysis. Highlights From the 2012 National
Sample Survey of Nurse Practitioners. Rockville, Maryland: U.S. Department of Health and Human
Services, 2014, 2014.
57. OECD;. OECD Health Statistics 2015. Definitions, Sources and Methods. Physicians licensed to
practice OECD, OECD Health Statistics 2015, 2015 July 2015. Report No.
58. OECD;. OECD Health Statistics 2015. Definitions, Sources and Methods. Professionally active
physicians. OECD, OECD Health Statistics 2015, 2015.
59. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2005. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2005.
60. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2006. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2006.
61. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2007. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2007.
62. Nursing Council of New Zealand. Annual Report 2009. Wellington, New Zealand: 2009.
63. Nursing Council of New Zealand. Annual Report 2010. Wellington, New Zealand: 2010.
64. Nursing Council of New Zealand. Annual Report 2011. Wellington, New Zealand: 2011.
65. Nursing Council of New Zealand. Annual Report 2012. Wellington, New Zealand: 2012.
66. Nursing Council of New Zealand. Annual Report 2013. Wellington, New Zealand: 2013.
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67. Nursing Council of New Zealand. Annual Report 2014. Wellington, New Zealand: 2014.
68. Nursing Council of New Zealand. Report of the Nursing Council of New Zealand for the year
ended 31 March 2008. Presented to the Minister of Health pursuant to Section 134 of the Health
Practitioners Competence Assurance Act 2003. Wellington, New Zealand: 2008.
69. Spitzer WO, Sackett DL, Sibley JC, Roberts RS, Gent M, Kergin DJ, et al. The Burlington
randomized trial of the nurse practitioner. N Engl J Med. 1974;290(5):251-6.
70. van der Biezen M, Schoonhoven L, Wijers N, van der Burgt R, Wensing M, Laurant M.
Substitution of general practitioners by nurse practitioners in out-of-hours primary care: a quasi-
experimental study. J Adv Nurs. 2016.
71. Wijers N, van der Burgt R, Laurant M. Verpleegkundig Specialist biedt kansen.
Onderzoeksrapport naar de inzet van de verpleegkundig specialist op de spoedpost in Eindhoven.
[Specialist Nursing offers opportunities. Research report into the use of the specialist nurse at the
emergency station in Eindhoven]. Nijmegen: IQ healthcare, UMC St Radboud; Eindhoven: KOH
Foundation: 2013.
72. Laurant M. Out of hours primary care. International Innovation 2013 [cited 2015 December].
Available from:
http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant
.pdf.
73. DiCenso A, Bryant-Lukosius D, Martin-Misener R, Donald F, Abelson J, Bourgeault I, et al.
Factors enabling advanced practice nursing role integration in Canada. Nurs Leadersh (Tor Ont).
2010;23 Spec No 2010:211-38.
74. Minto R. Barriers on nurse practitioner journey. Nurs N Z. 2008;14(6):4.
75. Begley C, Murphy K, Higgins A, Cooney A. Policy-makers' views on impact of specialist and
advanced practitioner roles in Ireland: the SCAPE study. Journal of Nursing Management.
2014;22(4):410-22.
76. Scanlon A, Cashin A, Bryce J, Kelly JG, Buckely T. The complexities of defining nurse
practitioner scope of practice in the Australian context. Collegian. 2016;23(1):129-42.
77. Cashin A. Collaborative arrangements for Australian nurse practitioners: A policy analysis.
Journal of the American Association of Nurse Practitioners. 2014;26(10):550-4.
78. Parliament of New Zealand. Misuse of Drugs Amendment Regulations 2014. 2014/199. 2014.
79. van Meersbergen D. Task-shifting in the Netherlands. World Medical Journal (WMA).
2011;57(4):126-30.
80. Phillips SJ. 28th Annual APRN Legislative Update: Advancements continue for APRN practice.
Nurse Pract. 2016;41(1):21-48.
81. Kroezen M, van Dijk L, Groenewegen PP, Francke AL. Nurse prescribing of medicines in
Western European and Anglo-Saxon countries: a systematic review of the literature. BMC Health Serv
Res. 2011(10):2011 May 27;11:127.
82. Government of Canada. Controlled Drugs and Substances Act. New Classes of Practitioners
Regulations. Canada Gazette. 2012;146(24).
83. Australian Government. Health Legislation Amendment (Midwives and Nurse Practitioners)
Act 2010. No. 29, 2010. C2010A00029. 2010.
84. Phillips SJ. 27th Annual APRN legislative update: advancements continue for APRN practice.
Nurse Pract. 2015;40(1):16-42.
85. Ono T, Lafortune G, Schoenstein M. Health Workforce Planning in OECD Countries: A Review
of 26 Projection Models from 18 Countries. OECD Health Working Papers [Internet]. 2013 October
2015 [cited 2015 October]; No. 62.
86. American College of Physicians. Nurse Practitioners in Primary Care. Philadelphia: American
College of Physicians, 2009.
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Sources: Authors’ calculations, based on the TaskShift2Nurses Survey 2015 and the following data sources: (37, 46, 51-55),
Notes: *2015: except for Canada, Ireland: 2014; Data on RNs include NPs, U.S.=United States, NP= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active, R=Registered/Licensed to practice, RNs=Registered Nurses, Caveats: Netherlands (nurse specialists): an estimated 12 test accounts are in the
database (0.4%) that cannot be filtered out (personal communication, with registry advisor at Verpleegkundig Specialisten Register, 29 January 2016).
Figure 1: Total number of NPs 279x215mm (300 x 300 DPI)
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Sources: Authors’ calculations, based on the following data sources: (37, 51-56), Data on physicians based on the OECD 2015 database (45), drawn from the following primary data sources: United States: American Medical Association (AMA); Canada: Canadian Institute for Health Information (CIHI); Netherlands: The BIG register, Australia: Australian Institute of Health and Welfare (AIHW), New Zealand: Medical Council Medical
Register (57, 58).
Notes: *Year 2013; except for Ireland (2014), United States (2012) depending on years covered by OECD physician data; NPs= Nurse Practitioner, N=total number, P=Practicing, PA=Professionally Active,
R=Registered/Licensed to practice, U.S.=United States, Caveats: Netherlands (Nurse specialists): an estimated 12 test accounts are in the database that cannot be filtered out (personal communication, with
registry advisor at Verpleegkundig Specialisten Register, 29 January 2016). Figure 2: Nurse Practitioner d 279x215mm (300 x 300 DPI)
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Supplement
A descriptive, cross-country analysis of the nurse practitioner
workforce in six countries: size, growth, physician substitution potential
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Table of Content
1. Information on the literature scoping review ........................................................................................ 3
1.1 Background on literature scoping reviews ........................................................................................ 3
1.2 Research questions, search strategy and data analysis ...................................................................... 3
2. Extent of NPs substituting fully or partially for physicians: overview of empirical studies................. 7
3. Quality of the evidence ....................................................................................................................... 10
4. References ........................................................................................................................................... 11
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1. Information on the literature scoping review
1.1 Background on literature scoping reviews
Literature scoping reviews have evolved over the last 20 years as an additional method to
systematic literature reviews for searching the literature and synthesising the evidence on a
specific topic, concept or research question (1-3). While systematic literature reviews usually
focus on narrowly defined research questions, usually following PICO elements (Participants,
Interventions, Comparisons, Outcomes) (4), literature scoping reviews start at an earlier stage
and with a broader scope, allowing for a broader approach to research questions or objectives (2,
3). Research questions are therefore typically defined per PCC (Population, Concept, Context)
instead of PICO elements (3). According to Cacchione (1), there are three distinctive features of
scoping reviews, first to map the research and key concepts underpinning a research question or
concept, second, to provide a synthesis and analysis of a wide range of research and grey or non-
research material and third, include various, heterogeneous sources instead of focusing on the
best evidence only.
We chose this study design to explore what evidence is available on the concept of physician
substitution effect, measuring the extent to which NPs can substitute partially or fully for
physicians. This research objective is relevant to workforce planners aiming at analysing the
potential of NPs for in expanding access to primary care, specific specialty areas or regions (e.g.
rural and remote areas). We aimed to identify all existing evidence in the field, instead of
restricting the review to Randomised Controlled Trials (RCTs) or other high-quality studies only.
We followed the methods established by the Joanna Briggs Institute’s manual on conducting
scoping reviews (3).
1.2 Research questions, search strategy and data analysis
Review question(s)
The following research question guided the review based on the PCC elements (Population,
concept, context):
What evidence exists on the concept of substitution, defined by Nurse Practitioners substituting
fully or partially for physicians with a focus on primary care, focusing on studies conducted in
six countries (Australia, Canada, Ireland, Netherlands, New Zealand, and the United States)?
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Literature search
The literature search covered Medline, CINAHL, Google Scholar, and grey literature, to identify
what studies, concepts and literature exists that have quantified the extent to which NPs are able
to substitute for physicians. We deliberately aimed to cover literature from peer-reviewed
journals and grey literature to explore what information is available. In addition, we performed
snowballing and asked country experts for additional information.
Inclusion criteria of the search:
- All studies (irrespective of the empirical method/methodology used) that quantify the
extent of advanced practice of NPs to estimate their potential in substituting for
physicians. The operational definition included the following: “studies calculating either
the percentage of typical medical activities that can be safely performed by NPs; or
methods on the extent of services that can be provided by NPs” (5, 6).
- The review was restricted to NPs only (Nurse Specialists in the Netherlands) working in
primary care, such as family health, community health, including pediatric (routine)
services, all primary care provider models (solo, group practices, health centres),
including out-of-hours care, emergency ambulatory care
- Studies conducted in one of the following countries: Australia, Canada, Ireland,
Netherlands, New Zealand, and the United States
- Search was conducted in English language
- No restrictions on years
Exclusion criteria:
- Studies that did not calculate in quantitative measures/terms the extent to which NPs can
provide the same services as physicians, hence partially or fully substitute for physicians
- Studies conducted outside the six countries
- All care services provided that are inpatient care or specialty services, such as secondary
and tertiary care, including hospital care, rehabilitation (if inpatient), psychiatric care if
inpatient or outpatient, nursing homes
- Non-NP roles, such as Physician Assistants, Clinical Nurse Specialists, nurse anesthetists,
nurse midwives, practice nurses, registered nurses.
Types of studies
All relevant studies were included that evaluate or analyse the potential physician
substitution effect of NPs, including RCTs (randomised controlled trials), before-after
studies, or any other studies with physicians as comparator groups, including studies
published in peer-reviewed journals and grey literature.
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Search terms used
Search terms included various combinations of the MeSH terms and individual search terms
on the concept of physician substitution by nurse practitioners with a focus on primary care.
The following search terms were used:
Set #1 [NPs or similar advanced practice nursing roles]
"Nurse Practitioners"[Mesh] OR nurse practitioner* [TW] OR “advanced practice nurse”
[TW] OR “advanced practice registered nurse” [TW] OR “advanced nursing practice” [TW]
OR “nurse specialist” [TW] OR “nurse led” [TIAB] OR “nurse-led” [TIAB]
Set #2 [concept of substitution]
Substitut* [tw] OR visit [all] OR contribution [tw] OR task-shifting [tiab] OR task shifting
[tiab] OR task sharing [tiab] OR delegation [tiab] OR re-allocation [tiab] OR forecasting
[tiab] OR planning [tiab]
Set #3 [primary care]
"primary care" [Mesh] OR primary care [tw] OR community [tiab] OR primary health care
[tw] OR community health [tw]
Combined Set 1 AND Set 2 AND Set 3
The search was conducted covering all years up to May 30, 2016.
Search results
The search yielded a total of 1,022 results (through databases, google scholar, snowballing and
additional information by experts). After removal of duplicates (n=31), the titles of 991 records
were screened according to the exclusion criteria. Of those, 768 were excluded, of which the
major reasons were as follows: other, none NP roles (e.g. practice nurses, community nurses,
nurse anaesthesists; or other non-physician roles, e.g. physician assistants, or a mix of different
providers), no physician comparator group, no calculation or quantification of the “physician
substitution potential” (e.g. percent of all visits performed by NPs, % of physician tasks
performed by NPs, etc). In a next step, the abstracts of 223 records were examined of which the
full-text of 46 studies were screened. Out of those, five papers met the inclusion criteria and were
relevant, as they had provided some form of quantification of the extent of substitution effect
(three peer-reviewed journal articles, and two sources of grey literature) reporting findings from
three different empirical studies. The search was conducted in English, however, snowballing
and contacts with individual researchers resulted in few non-English publications, of which one
Dutch report was included.
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In addition, two reviews, published as a working paper and a book were identified (6, 7) that
aimed at providing an overview of studies quantifying the % of physician substitution potential.
They were excluded from the main results because they included several groups of non-
physician providers and did not exclusively focus on NPs. However, we provide an overview of
the findings below to set our findings in context.
Data analysis and synthesis involved the extraction of information on the country, research aims,
study design and year(s) of the study, service delivery settings, number and characteristics of
participants, and the results. A narrative synthesis was performed, pooled analysis was not
possible, due to the large heterogeneity of the studies and material identified.
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2. Extent of NPs substituting fully or partially for physicians: overview of empirical studies
Table S 1. Detailed overview of empirical studies on the percent of physician substitution effect by NPs
Country Aims/Purpose Study design
(Years) Setting Participants Results Reference
Canada To assess the
effects of
substituting
NPs for
physicians in
primary care
RCT (1971-
1972)
Two large
suburban
Ontario
family
practices
consisting
of 1
physician
and 1 NP
each.
Families
were
randomised
to care by a
physician or
NP. 529
families
(1,398
individuals)
randomised
to each
physician;
270 families
(765
individuals)
to each NP.
Total patient
N = 1,598
families
(4,325
individuals)
67% of all primary care patient visits could be
provided by NPs.
Care delivery was similar between physicians
and NPs. There were no statistically significant
differences between patients seen by NPs
compared to patients seen by physicians were
found in patient functional capacity, indexes of
social and emotional function, mortality, or
satisfaction with care.
Practices were able to increase practice size and
patient volume with the addition of an NP in the
practice.
(8)
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Netherlands To compare the
number of
patients and
caseloads
between NPs
and GPs in out-
of-hours
services
Quasi-
experimental
study (April
2011 to July
2012)
Out-of-
hours
primary
care
Intervention:
one NP and
four GPs,
control: five
GPs working
in out-of-
hours
services.
Total patient
N=12,092
from one GP
cooperative
extracted
from medical
records
75-83% of clinical activities in out-of-hours
primary care settings (weekend shifts in GP
practices) could be taken over by Nurse
Specialists (Verpleegkundig Specialist)
More than 77% of patients fit the scope-of-
practice of Nurse Practitioners (Verpleegkundig
Specialist) in out-of-hours care.
On average 16.3% of all patients were treated by
NPs, whereas 20.9% of patients were treated by
GPs. GPs were more likely than NPs to treat
older patients, patients with digestive,
cardiovascular and neurological complaints and
more urgent cases, whereas NPs treated more
patients with skin and respiratory diseases.
(9, 10)
(11)
U.S. To assess
practice
activities of
rural primary
care physicians
and NPs.
Self-report,
mailed survey
to a random
sample of
4,000
physicians and
3,000 NPs with
rural addresses
(all specialties)
(2011-2012)
Rural
primary
care in 13
states with
at least 2
from each
U.S. Census
Regions (4
regions).
Final sample
included 788
primary care
physicians
(response
rate: 25%);
and 918
primary care
NPs (40%)
75-93% of weekly primary care outpatient visits
can be provided by NPs.a
In the outpatient setting, primary care clinical
activitiesb were comparable between physicians
and NPs in the outpatient setting.
Average weekly outpatient visit quantity was
25% lower for NPs (p<0.001) than physicians,
this difference decreased to 10% for NPs
(P<0.001) compared to physicians in the
multivariate analyses.
(12)
Source: see directly in the table
Notes: NP = nurse practitioners; RCT = randomised controlled trial; GP = general practitioner a In an unadjusted regression model, NP average weekly number of outpatient visits was 75% of physician volume. In an adjusted model (age, sex,
geographic location, and practice setting), NP average weekly number of outpatient visits was 93% of physician volume. b On average, physicians conducted more well-child visits than NPs (12.6 vs. 7.4, p <0.001). Differences for prenatal visits and minor procedures
were non-significant.
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Table S 2. Overview of reviews on the percent of physician substitution effect by NPs (and other non-physician providers)
Country Aims/Purpose Study design
(Years) Setting Participants Results Reference
Reviews
U.S.-
focused
studies
To assess the
delegation of
primary care
office visits to
NPs and other
“health
practitioners”
Overview of
studies (Dates
of NP-focused
studies: 1968-
1974)
Primary
Care – adult
and
pediatric
17 studies
included with
7 focusing on
delegation of
visits to NPs.
75% of adult primary care and
90% of pediatric primary care
can be safely delegated to NPs
(7)
International
scope
(studies
from U.S.,
Canada,
UK)
To assess the
what
percentage of
physicians’
tasks can be
performed by
nurses by
synthesizing
the evidence on
doctor-nurse
substitution
Review of
studies
All care
settings
12 studies
including
several non-
physician
providers
(including
NPs, practice
nurses,
physician
assistants) in
intervention
group
30 to 70% of the tasks
performed by physicians could
be performed by nurses or other
non-physician providers
(including NPs, registered
nurses, practice nurses, other
practitioners)
(6)
Source: see directly in the table
Notes: NP = nurse practitioner, U.S.=United States
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3. Quality of the evidence
The quality of the records of studies included was highly variable, but mostly of limited quality.
Of the five relevant papers, three were studies published in peer-reviewed journals, and two other
sources were retrieved via google scholar and snowballing. The comparatively highest quality
study was one study in Canada which findings stem from a small RCT involving two Ontario
family practices (8). The study shows the smallest risk of bias compared to the other literature,
yet dates back more than 40 years and was based on a small provider base (8). One more recent
study, conducted in 2011-12 in the Netherlands was based on a quasi-experimental design, with
moderate to high risk of bias, from which three papers reported findings (9-11) with the main
paper being (11). Of the remaining source included from the U.S., one recent study was based on
a survey to over 7,000 physicians and NPs in rural areas, covering all specialty areas to assess
the extent of practice, frequency of visits and primary care physician substitution potential (12).
Yet, its generalisability is limited since focused on rural practice. In conclusion, the evidence
available to assess the extent to which NPs can substitute for physicians faces considerable
limitations, is based on few studies, one of which dates back more than 40 years, calling for
future research in the area.
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4. References
1. Cacchione PZ. The Evolving Methodology of Scoping Reviews. Clinical nursing research. 2016;25(2):115-9. 2. Armstrong R, Hall BJ, Doyle J, Waters E. Cochrane Update. 'Scoping the scope' of a cochrane review. Journal of public health (Oxford, England). 2011;33(1):147-50. 3. The Joanna Briggs Institute. The Joanna Briggs Institute Reviewers’ Manual 2015. Methodology for JBI Scoping Reviews. The Joanna Briggs Institute (JBI), 2015. 4. Higgins JPT, Green Se. Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0. The Cochrane Collaboration, 2011 updated March 2011. Report No. 5. Advisory Committee on Medical Manpower Planning (Capaciteitsorgaan). The 2013 Recommendations for Medical Specialist Training. In the medical, dental, clinical, technological and mental health areas of training. Utrecht2013 [cited 2015 September]. Available from: http://www.capaciteitsorgaan.nl/Portals/0/capaciteitsorgaan/publicaties/Capaciteitsplan%202013/DEFINITIEF%20hoofdrapport%20engels%20compl.pdf 6. Richardson G, Maynard A. Fewer doctors? More nurses? A review of the knowledge base of doctor-nurse substitution. York: Centre for Health Economics, York Health Economics Consortium, University of York, 1995 Contract No.: 135. 7. Record J. Staffing in Primary Care in 1990: Physician replacement and cost savings. New York: Springer Publishing Company; 1981. 8. Spitzer WO, Sackett DL, Sibley JC, Roberts RS, Gent M, Kergin DJ, et al. The Burlington randomized trial of the nurse practitioner. N Engl J Med. 1974;290(5):251-6. 9. Wijers N, van der Burgt R, Laurant M. Verpleegkundig Specialist biedt kansen. Onderzoeksrapport naar de inzet van de verpleegkundig specialist op de spoedpost in Eindhoven. [Specialist Nursing offers opportunities. Research report into the use of the specialist nurse at the emergency station in Eindhoven]. Nijmegen: IQ healthcare, UMC St Radboud; Eindhoven: KOH Foundation: 2013. 10. Laurant M. Out of hours primary care. International Innovation 2013 [cited 2015 December]. Available from: http://rcpsc.medical.org/publicpolicy/imwc/out_of_hours_primary_care_interview_miranda_laurant.pdf. 11. van der Biezen M, Schoonhoven L, Wijers N, van der Burgt R, Wensing M, Laurant M. Substitution of general practitioners by nurse practitioners in out-of-hours primary care: a quasi-experimental study. J Adv Nurs. 2016. 12. Doescher MP, Andrilla CHA, Skillman SM, Morgan P, Kaplan L. The Contribution of Physicians, Physician Assistants, and Nurse Practitioners Toward Rural Primary Care Findings From a 13-State Survey. Medical Care. 2014;52(6):549-56.
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Correction: Descriptive, cross-country analysis of the nursepractitioner workforce in six countries: size, growth,physician substitution potential
Maier CB, Barnes H, Aiken LH, et al. Descriptive, cross-country analysis of the nursepractitioner workforce in six countries: size, growth, physician substitution potential.BMJ Open 2016;6:e011901. Complete publication details of references 36, 39–41, 53,77, 81 and 82 are given below.36. Maier CB, Aiken LH. Task-shifting from physicians to nurses in primary care in
39 countries: a cross-country comparative study. Eur J Public Health 2016. [ePub aheadof print 2 Aug 2016]. doi:10.1093/eurpub/ckw09839. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May
2014. 29-1171 Nurse Practitioners. Bureau of Labor Statistics (BLS), 2014. http://www.bls.gov/oes/current/oes291171.htm (accessed Dec 2015).40. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May
2012. 29-1171 Nurse Practitioners. Bureau of Labor Statistics (BLS), 2012. http://www.bls.gov/oes/current/oes291171.htm (accessed Dec 2015).41. U.S. Bureau of Labor Statistics. Occupational Employment and Wages, May
2013. 29-1171 Nurse Practitioners. Bureau of Labor Statistics (BLS), 2013. http://www.bls.gov/oes/current/oes291171.htm (accessed Dec 2015).53. Nursing and Midwifery Board of Australia. Statistics. 2015 June 2015. Report
No. http://www.nursingmidwiferyboard.gov.au/About/Statistics.aspx (accessed Dec 2015).77. Parliament of New Zealand. Misuse of Drugs Amendment Regulations 2014. 2014/
199. 2014. http://www.legislation.govt.nz/regulation/public/2014/0199/latest/DLM6156029.html?search=qs_regulation%40deemedreg_Misuse+of+drugs+act_resel_25_h&p=1 (accessed Dec2015).81. Government of Canada. Controlled Drugs and Substances Act. New Classes of
Practitioners Regulations. Canada Gazette. 2012;146. http://www.gazette.gc.ca/rp-pr/p1/2012/2012-05-05/html/reg1-eng.html (accessed Dec 2015).82. Australian Government. Health Legislation Amendment (Midwives and Nurse
Practitioners) Act 2010. No. 29, 2010. C2010A00029. 2010. https://www.legislation.gov.au/Details/C2010A00029 (accessed Dec 2015).
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