measuring disability prevalence daniel mont, hdnsp disability and development team june 6, 2007
TRANSCRIPT
World Bank and Disability – What is the link?World Bank and Disability – What is the link?
The World Bank’s mission is to eliminate povertyThe World Bank’s mission is to eliminate poverty Disability leads to poverty, and poverty leads to Disability leads to poverty, and poverty leads to
disabilitydisability Disability affects not just disabled people, but Disability affects not just disabled people, but
their families and communitiestheir families and communities Doing a good job on poverty alleviation requires Doing a good job on poverty alleviation requires
taking disabled people into accounttaking disabled people into account
Problems with existing data
Often not available Definitions and measures not
standard and often outdated Quality is poor
Prevalence Rates Vary Dramatically (Censuses)
United States 19.4%
United Kingdom 12.2%
Uganda 3.5%
Mexico 2.3%
India 2.1%
Kenya 0.7%
Prevalence Rates Vary Dramatically – (Surveys)
New Zealand 20.0%
Spain 15.0%
Ecuador 12.1%
Nicaragua 10.3%
China 5.0%
Egypt 4.4%
Medical Model vs. Social Model
Medical model – Disability is a physical, mental or psychological health condition that limits a person’s activities
Social model – Disability arises from the interaction of a person’s functional status with the environment
Medical versus Social Model
PERSONAL vs. SOCIAL Medical care vs. Social integration Individual treatment vs. Social action Professional help vs. Individual and collective
responsibility Personal adjustment vs. Environmental
adjustment Behavior vs. Attitude Care vs. Human rights Individual adaptation vs. Social change
WHO’s International Classification of Functioning, Disability and Health (ICF) Incorporates social model approach Describes facets of human functioning that
may be affected by a health condition Purpose:
provide a scientific basis for the consequences of health conditions
establish a common language to improve communications
permit comparisons of data across countries and health care disciplines,
provide a systematic coding scheme for health information systems
ICF Domains – Body Function and Structure
Physiological and psychological function of body systems
Very specific recording of detailed functional abilities and impairments
Not linked to cause. For example, fluency and rhythm of speech functions – could be from stuttering, stroke, or autism
Activities and Participation
Describes individual’s functioning as a whole person
Range from Basic to Complex Basic: e.g., walking, eating, and bathing Complex: e.g., work and schooling
Activities – tasks an individual can do that require multiple body functions
Participation – higher order activities that involve integration in the community
ICF is a Functionally Based System
ICF does not measure disability It describes people’s functional abilities in various
domains
Health conditions that affect functional status are not part of classification system
Disability is not an “all or nothing” concept Disability arises out of the environmental
context
Health Condition Health Condition ((disorder/diseasedisorder/disease))
International Classification of International Classification of Functioning, Disability and Health Functioning, Disability and Health
(ICF)(ICF)
Environmental Environmental FactorsFactors
Personal Personal FactorsFactors
Body Body function&structurefunction&structure (Impairment(Impairment))
ActivitiesActivities(Limitation)(Limitation)
ParticipationParticipation(Restriction)(Restriction)
Why not ask this old question?
Do you have a physical, mental, or emotional health condition that limits the amount or type of work you can do?
Because…
In some sense, the answer for everyone is “YES”
The answer is a function of the environment the respondents live in Physical environment Cultural environment Policy environment
The answer is a function of their particular circumstances at the time
The question is very complex and easily misinterpreted
Under counts what most people consider disability
People think of disability as very serious and won’t report minor or moderate disabilities
“Disability” creates shame and stigma so people do not want to identify themselves that way, especially for mental and psychological
People think of disability relative to their expectations of normal functioning so it undercounts the elderly
Why not ask detailed diagnosis questions?
Many people don’t have or don’t know their diagnosis Some diagnoses have intense stigma A diagnosis doesn’t tell you much about ability to
function Can miss age related disabilities If people have multiple diagnoses they’ll often report
only one The one with less stigma The one that occurred first The one that’s most visible
Ability and willingness to report often depends on their interaction with health services and thus other socio-demographic factors
Census-based Disability Rates
Do you have a disability?
Nigeria 0.5
Jordan 1.2
List of conditions
Mexico 1.8
Uganda 3.5
Activity Based
Poland 10.0
Brazil 14.5
Where we focus on this model depends on the purpose of measurement
Health Condition Health Condition ((disorder/diseasedisorder/disease))
Environmental Environmental FactorsFactors
Personal Personal FactorsFactors
Body Body function&structurefunction&structure (Impairment(Impairment))
ActivitiesActivities(Limitation)(Limitation)
ParticipationParticipation(Restriction)(Restriction)
National prevalence rates
Internationally comparable Capture broad spectrum of those with
disabilities Questions suitable for census To examine the relationship between
disability and socio-economic outcomes
Equalization of Opportunity
UN Washington Group concluded that Equalization of Opportunities was most appropriate for a census.
So ask participation questions? No. That identifies the segment of the
population that is not participating so can’t look at progress of inclusion
Not internationally comparable
Activity level questions indicate whether a person is having difficulty with important tasks
If these activity limitations are correlated with outcome measures (e.g., poverty) this indicates there are important barriers to participation
WG Questions Because of a physical, mental or emotional health
condition… Do you have difficulty seeing, even if wearing
glasses? Do you have difficulty hearing, even if wearing
hearing aid/s? Do you have difficulty walking or climbing stairs? Do you have difficulty remembering or
concentrating Do you have difficulty with self-care, such as
washing all over or dressing? Do you have difficulty communicating (for example,
understanding or being understood by others)? Response categories: No, Some, A lot, Unable
Cognitive Testing
To examine interpretation of questions
Conducted in about 15 countries Performed very well Issues:
Difficulty with glasses and hearing aid/s clause
Communication question
Field Testing
Vietnam and South Africa UNESCAP testing in Philippines, Fiji,
India, Indonesia and Mongolia Again, responses fairly robust
Responses
Scaled responses No, Some, A lot, and Unable Allows user to shift threshold as desired Captures heterogeneity of disability
0
20
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180
1 5 9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 82 86 90 94 98 102 108 112 119 126 143 161
Num
ber d
isab
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Num
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isab
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Disabled
Non-disabled
Activity Limitation Scores - Zambia
Recommendations for General Prevalence Measures
Questions should be based on functionality Questions should focus on core activities
Equalization of opportunity International comparability
Do not use the word “disability” Responses should be scaled A range of prevalence should be reported
for various levels of severity, rather than a single prevalence rate
Do you have difficulty walking or climbing steps?
PctCumulative
Pct
Some difficulty 16.6 16.6
A lot of difficulty 5.2 21.8
Unable 0.7 22.5
Mobility Limitations in Vietnam
UNESCAP Field Testing
India Indonesia MongoliaSeeing
Mild 4.7 14.9 12.4Severe/Unable 4.4 7.3 4.2
Cognitive
Mild 8.1 16.3 9.7Severe/Unable 3.7 2.9 4.0
Disability Rates in LAC
Total Male Female
Brazil 14.5 13.7 15.3
Ecuador 12.1 11.8 12.4
Nicaragua 10.3 9.1 11.3