Queensland University of Technology

School of Nursing

Institute of Health and Biomedical Innovation

Opioid-Taking Self-Efficacy in Taiwanese Outpatients with Cancer Pain

Shu-Yuan Liang RN, BSN, MSN

Submitted for the Award of Doctor of Philosophy

September 2007

i

Keywords

Decision making

Analgesic-taking self-management

Self-efficacy

Confidence

Cancer pain

Pain management

ii

Abstract

Despite the fact that as many as 80-90% of patients with cancer pain can be

effectively treated using pharmacological therapies and other advanced approaches,

31% to 85% of cancer patients in Taiwan still experience varying levels of pain. Pain

is one of the symptoms that patients fear most; it overwhelms all aspects of patients’

lives and creates a sense of uncertainly and hopelessness. Pain control is, therefore, a

high priority in the treatment of cancer patients. Pharmacological therapy is the

cornerstone of cancer pain management. With the current trend toward outpatient

care, many patients are being required to assume greater responsibility for self-

management of prescribed analgesics at home to deal with the variable and complex

nature of cancer pain and side effects of opioids. Patients however, have

misconceptions regarding analgesics and a series of difficulties when attempting to

put a pain management regimen into practice.

This research addressed the hypothesis that self-efficacy beliefs might play an

important role in analgesic adherence and pain experience in Taiwanese outpatients

with cancer. The purpose of this study was to develop a scale to measure the self-

efficacy expectations relating to opioid-taking in Taiwanese outpatients with cancer.

Another purpose was to explore how opioid-taking self-efficacy and beliefs about

opioid analgesics contribute to patients’ analgesic adherence and pain experience in

Taiwanese outpatients with cancer.

In the first stage semi-structured interviews were conducted to collect data from a

purposeful sample (n=10) of oncology outpatients from two teaching hospitals in the

Taipei area of Taiwan. The purpose of this phase was to identify behaviours and

iii

situational impediments associated with analgesic taking. Findings from this phase

were used to develop a scale to measure opioid-taking self-efficacy. In the second

stage a pilot test with a convenience sample (n=30) was conducted to test the validity

and reliability of the new scale and to identify the feasibility of using the scale in a

cross-sectional survey. In the third stage a cross-sectional survey was undertaken

(n=92) to describe pain experiences, analgesic adherence, beliefs about opioid

analgesics, and opioid-taking self-efficacy in Taiwanese outpatients with cancer and

to explore how opioid-taking self-efficacy and beliefs about opioid analgesics

contributed to analgesic adherence and pain experience.

Results of this study highlight an important issue – under-treatment of cancer pain in

this group of Taiwanese outpatients. As well, low adherence rates to opioid

analgesics in cancer outpatients arose as an important issue in this study. A range of

misconceptions about using opioids for pain was also common amongst the sample.

Despite these misconceptions, patients reported being moderately confident in their

ability to perform self-management behaviours related to their prescribed opioid-

taking. Results of this research supported the notion that patients’ self-efficacy in

relation to taking their prescribed opioid regimen was a significant independent

predictor of patients’ adherence behaviour and pain relief, but not of pain severity.

Beliefs about opioid analgesics were also an independent predictor of patients’

adherence, but not of pain relief or pain severity. In addition, findings from this study

provided support for the validity and reliability of the opioid-taking self-efficacy

scale.

iv

Results suggested there is a need for systematic assessment of beliefs affecting

patients’ opioid adherence behaviours for cancer pain control, including perceived

personal self-efficacy and beliefs about opioid analgesics. Educational programs that

focus on overcoming patients’ misconceptions (beliefs) about taking opioid

analgesics may be particularly beneficial. In addition, this study advocates that

conducting self-efficacy-enhancing interventions may improve medication adherence

for patients and therefore pain relief. More research is needed to demonstrate the

construct validity of the self-efficacy scale and to evaluate self-efficacy enhancing

interventions in cancer pain management.

v

Table of Contents

Keywords ............................................................................................................ i

Abstract.............................................................................................................. ii

Table of Contents .............................................................................................. v

List of Appendices ............................................................................................ ix

List of Tables ..................................................................................................... x

List of Figures.................................................................................................. xii

Statement of Original Authorship ................................................................xiii

Acknowledgements......................................................................................... xiv

Chapter 1: Introduction ................................................................................... 1 1.0 Introduction................................................................................................... 1 1.1 Background and Significance of the Study................................................... 1

1.1.1 The Prevalence of Cancer Pain ............................................................ 1 1.1.2 Impact of Cancer Pain.......................................................................... 2 1.1.3 Cancer Pain in Taiwan ......................................................................... 3

1.2 Problem Statement and Significance of this Study....................................... 4 1.3 Aims .............................................................................................................. 8

1.3.1 Aims of the Research ........................................................................... 8 1.3.2 Research Questions .............................................................................. 8

1.4 Research Design and Methods ...................................................................... 9 1.5 Overview of the Thesis ............................................................................... 11 Chapter 2: Conceptual Model of Pain and Pain Management................... 14 2.0 Introduction................................................................................................. 14 2.1 Definition of Pain........................................................................................ 14 2.2 Multidimensional Components of Pain....................................................... 15

2.2.1 Physiological Component of Pain...................................................... 16 2.2.2 Sensory Component of Pain............................................................... 17 2.2.3 Affective Component of Pain............................................................. 18 2.2.4 Cognitive Component of Pain............................................................ 18 2.2.5 Behavioural Component of Pain ........................................................ 22 2.2.6 Sociocultural Component of Pain ...................................................... 24

2.3 Multidimensional Approaches to Pain Management .................................. 26 2.4 Evidence Review on Difficulties with Patients’ Adherence to

Pharmacological Therapies ......................................................................... 30 2.4.1 The Concepts of Adherence ............................................................... 30 2.4.2 Practical Problems with Adherence to Prescribed Medications ........ 32

2.4.2.1 Obtaining the Prescribed Medications .................................. 32 2.4.2.2 Accessing Information .......................................................... 33 2.4.2.3 Tailoring Prescribed Regimens to Meet Individual Needs .... 34 2.4.2.4 Managing Side Effects ........................................................... 37

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2.4.2.5 Cognitively Processing Information ..................................... 38 2.4.2.6 Managing Multiple Symptoms Simultaneously..................... 38

2.5 Summary of Literature ............................................................................... 39 Chapter 3: Theoretical and Empirical Approaches to Understanding Self-

Efficacy........................................................................................... 41 3.0 Introduction ................................................................................................ 41 3.1 Self-Efficacy Construct............................................................................... 41 3.2 Theoretical Concepts................................................................................... 44

3.2.1 Self-Efficacy Models ......................................................................... 44 3.2.2 Efficacy Expectations and Outcome Expectations ............................ 45 3.2.3 Information Sources of Efficacy Expectations ................................. 48 3.2.4 Cultural and Personal Factors Influencing Efficacy Expectations..... 49

3.3 Relationships between Concepts in Self-Efficacy Model........................... 51 3.3.1 Opioid-Taking Self-Efficacy Expectations ........................................ 52 3.3.2 Efficacy Expectations and Adherence Behaviour.............................. 53 3.3.3 Efficacy Expectations and Pain Outcomes ........................................ 54 3.3.4 Personal and Cultural Factors Influencing Efficacy Expectations..... 55

3.3.4.1 Personal Factors Influencing Efficacy Expectations.............. 55 3.3.4.2 Efficacy Expectations amongst the Taiwanese Population.... 56

3.4 Measuring Efficacy Expectations .............................................................. 58 3.5 Critique of Self-Efficacy Theory ............................................................... 61 3.6 Summary .................................................................................................... 64 Chapter 4: Methodology................................................................................ 65 4.0 Introduction................................................................................................ 65 4.1 Research Design......................................................................................... 65 4.2 Stage One: Semi Structured Interviews ..................................................... 65

4.2.1 Aim.................................................................................................... 65 4.2.2 Research Question............................................................................. 66 4.2.3 Research Design................................................................................ 66 4.2.4 Interview Guide................................................................................. 66 4.2.5 Sample, Procedure, and Setting ........................................................ 68 4.2.6 Data Analysis .................................................................................... 69 4.2.7 Rigour of the Interviews ................................................................... 72 4.2.8 Scale Development ........................................................................... 74

4.3 Stage Two: Pilot Testing of the Scale ........................................................ 75 4.3.1 Aims .................................................................................................. 75 4.3.2 Research Questions ........................................................................... 75 4.3.3 Research Design................................................................................ 75 4.3.4 Research Population.......................................................................... 76 4.3.5 Sampling Strategy, Sample Size, and Procedure .............................. 76

4.3.5.1 Assessing Face Validity and Reliability of the Scale............. 76 4.3.5.2 Assessing Content Validity of the Scale ............................... 78

4.3.6 Data Analysis .................................................................................... 80 4.4 Stage Three: Cross-Sectional Survey......................................................... 81

4.4.1Aims ................................................................................................... 81 4.4.2 Research Questions ........................................................................... 81 4.4.3 Research Design................................................................................ 82 4.4.4 Sample Size and Power Analysis...................................................... 82

vii

4.4.5 Sampling Strategy and Procedure ..................................................... 83 4.5 Definitions of Study Variables................................................................... 85 4.6 Instrument/ Measurement Strategy ............................................................ 86

4.6.1 Instrument Translation ...................................................................... 86 4.6.2 Measures/ Assessment tools.............................................................. 87

4.6.2.1 Sociodemographic Variables ................................................ 87 4.6.2.2 Opioid-Taking Self-Efficacy................................................. 87 4.6.2.3 Pain and Opioid Analgesic Beliefs ....................................... 88 4.6.2.4 Analgesic Adherence ............................................................ 88 4.6.2.5 Pain Experience..................................................................... 91

4.7 Data Analysis Plan ..................................................................................... 92 4.7.1 Preanalysis Phase .............................................................................. 92 4.7.2 Analysis Phase .................................................................................. 93

4.8 Research Ethics / Statement ....................................................................... 94 4.9 Summary .................................................................................................... 95 Chapter 5: Interview Findings and Pilot Testing........................................ 97 5.0 Introduction................................................................................................ 97 5.1 Stage One: Development of the Opioid-Taking Self-Efficacy Scale.......... 97

5.1.1 Framework for the Semi Structured Interview................................... 97 5.1.2 Sample Characteristics of the Semi-Structured Interview ................. 99 5.1.3 Findings from the Semi-Structured Interviews ................................ 100

5.1.3.1 Communicating about Pain and Analgesic-Taking ............. 102 5.1.3.2 Tailoring Medication Regimens........................................... 106 5.1.3.3 Taking Analgesics According to Schedule .......................... 111 5.1.3.4 Acquiring Help..................................................................... 113 5.1.3.5 Managing Treatment Related Concerns............................... 116

5.2 Item Development for the Opioid Self-Efficacy Scale ............................. 120 5.2.1 Integrating Items from Literature Review into the Generated Scale 120 5.2.2 Scaling Format and Scoring Procedures .......................................... 124

5.3 Expert Review of the Scale ....................................................................... 124 5.3.1 Native English Speaking Experts Review of the Scale.................... 124 5.3.2 Scale Translation.............................................................................. 127 5.3.3 Native Chinese Speaking Experts Review of the Scale ................... 128

5.4 Stage Two: Pilot Test ................................................................................ 131 5.4.1 Sample Characteristics of Pilot Test ................................................ 131 5.4.2 Feasibility......................................................................................... 134 5.4.3 Internal Consistency of the Opioid-Taking Self-Efficacy Scale...... 134 5.4.4 Test-Retest Reliability of the Opioid-Taking Self-Efficacy Scale... 135

5.5 Summary ................................................................................................... 137 Chapter 6: Results of Cross-Sectional Survey............................................ 138 6.0 Introduction............................................................................................... 138 6.1 Stage Three: Cross-Sectional Survey........................................................ 138

6.1.1 Sample Characteristics for the Cross-Sectional Survey................... 138 6.2 Evaluating Construct Validity of the Self-Efficacy Scale......................... 142

6.2.1 Sample Size...................................................................................... 142 6.2.2 Factor Analysis for the Opioid-Taking Self-Efficacy Items ............ 145 6.2.3 Coefficient Alpha for the Opioid-Taking Self-Efficacy Scale......... 158

viii

6.3 Coefficient Alpha for the Brief Pain Inventory and the Pain Opioid Analgesics Beliefs Scale ........................................................................... 160

6.4 Analysis of Normality ............................................................................... 160 6.5 Results of Research Questions .................................................................. 161 6.6 Summary ................................................................................................... 183 Chapter 7: Discussion ................................................................................... 185 7.0 Introduction............................................................................................... 185 7.1 Major Findings of the Study: Pain Experience amongst Taiwanese

Outpatients with Cancer............................................................................ 185 7.2 Major Findings of the Study: Predictors of Pain Outcomes in Taiwanese

Outpatients with Cancer............................................................................ 190 7.2.1 Adherence to Analgesics amongst Taiwanese Outpatients with

Cancer .............................................................................................. 191 7.2.2 Beliefs about Opioid Analgesics in Taiwanese Outpatients with

Cancer .............................................................................................. 192 7.2.2.1 Describing Beliefs about Opioid Analgesics in Taiwanese

Outpatients with Cancer....................................................... 192 7.2.2.2 Relationships between Beliefs about Opioid Analgesics,

Analgesic Adherence, and Pain Experience in Taiwanese Outpatients with Cancer....................................................... 195

7.2.3 Opioid-Taking Self-Efficacy in Taiwanese Outpatients with Cancer .......................................................................................................... 197 7.2.3.1 Levels of Self-Efficacy in Taiwanese Outpatients with

Cancer .................................................................................. 197 7.2.3.2 Relationships between Self-Efficacy, Analgesic Adherence,

and Pain Experience in Taiwanese Outpatients with Cancer .............................................................................................. 202

7.3 Strengths and Limitations of the Study..................................................... 207 7.4 Implications of the Study and Recommendations for Future Research.... 210 7.5 Conclusion ................................................................................................ 217 Appendices ..................................................................................................... 219 References ...................................................................................................... 265

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List of Appendices

Appendix A: Study Information Sheet for Interview (Stage 1) ...................... 219

Appendix B: Study Information Sheet for Survey (Stage 2 & Stage 3) ......... 220

Appendix C: Study Consent Form (Stage1, 2 & 3) ........................................ 221

Appendix D: Consent Form for Transcription................................................ 222

Appendix E: Instruction Sheet ........................................................................ 223

Appendix F: Demographic Form .................................................................... 224

Appendix G: Medical Characteristic Form..................................................... 225

Appendix H: Brief Pain Inventory (BPI- Short Form) Questionnaire ............ 226

Appendix I: Pain Opioid Analgesics Beliefs Scale-Cancer (POABS-CA)..... 228

Appendix J: Opioid-Taking Self-Efficacy Scale- Cancer (OTSES-CA) ........ 229

Appendix K: Form for Collecting Prescribed Opioid Analgesics .................. 232

Appendix L: Permission for Using Brief Pain Inventory (BPI-Short Form)

Questionnaire ............................................................................. 233

Appendix M: Permission for Using Pain Opioid Analgesics Beliefs

Scale-Cancer (POABS-CA) ....................................................... 234

Appendix N: Interview Questions................................................................... 235

Appendix O: Opioid-Taking Self-Efficacy Scale for Expert Panellists

Review ....................................................................................... 236

Appendix P: Consent Form for Agreement to Participate on Expert Panel.... 243

Appendix Q: Consent Form for Agreement to Participate on Expert Panel ... 244

Appendix R: Consent Form for Agreement to Participate on Expert Panel ... 245

Appendix S: Consent Form for Agreement to Participate on Expert Panel.... 246

Appendix T: Consent Form for Agreement to Participate on Expert Panel ... 247

Appendix U: CVI of each item in the Opioid-Taking Self-Efficacy Scale

(English Version) ...................................................................... 248

Appendix V: CVI of each item in the Opioid-Taking Self-Efficacy Scale

(Chinese Version)...................................................................... 252

Appendix W: Structured Interview Guides for Pilot Test............................... 254

Appendix X: Permission to Tape Interviews .................................................. 255

Appendix Y: Ethics Committee Approval ...................................................... 256

Appendix Z: The Chinese Version of Questionnaires in Present Research.... 257

x

List of Tables

Table 4.1 Variable, Conceptual Definition, and Operational Definition .......... 85

Table 5.1 Characteristics of Interview Participants for Stage 1 (N = 10) ....... 100

Table 5.2 Categories of Behaviours and Situations Associated with

Opioid-Taking Self-Efficacy............................................................ 101

Table 5.3 Preliminary Items Developed from Stage One Interviews

and Literature Review...................................................................... 121

Table 5.4 Number of Items Generated from the Interview Findings

and the Literature Review ................................................................ 123

Table 5.5 Suggestions of Native English Speaking Experts on the

Preliminary 36-Item Self-Efficacy Scale ........................................ 126

Table 5.6 Summary of Changes Made to Items as a Result of Translation into

Chinese Version of the Self-Efficacy Scale ..................................... 128

Table 5.7 Suggestions of Native Chinese Speaking Experts on the 35-Item

Opioid-Taking Self-Efficacy Scale ................................................. 130

Table 5.8 Demographic Variables of the Sample for Stage 2 (N = 30) .......... 131

Table 5.9 Medical Characteristics of the Sample for Stage 2 (N = 30) .......... 133

Table 5.10 Cronbach’s Alpha Values of the Opioid-Taking Self-Efficacy

Total Scale and Subscales (Original Version) (N=30)..................... 135

Table 5.11 Test-Retest Reliability of Opioid-Taking Self-Efficacy

Total Scale and Subscales (Original Version) (N=30)..................... 136

Table 6.1 Demographic Data of the Sample for Stage 3 (N = 92).................. 139

Table 6.2 Medical Characteristics of the Sample for Stage 3 (N = 92) .......... 141

Table 6.3 Components of Factors and Communality for the 35-Item

Self-Efficacy Scale (N=92) (Initial Factor Analysis) ...................... 146

Table 6.4 Summary of Items Loading on the Factors and Item Inclusion

for the 35-Item Self-Efficacy Scale (Initial Factor Analysis) .......... 151

Table 6.5 Components of Factors and Communalities for the 31-Item

Self-Efficacy Scale (N=92) (Final Factor Analysis)....................... 153

able 6.6 Correlations between Factor4, 5, and 6 of the 31-Item Self-

Efficacy Scale (N=92)...................................................................... 155

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Table 6.7 Items Loading on the Factors along with Initial Conceptual

Description for the 31-Item Self-Efficacy Scale.............................. 156

Table 6.8 Subscale Names and Item Descriptions for the 30-Item

Self-Efficacy Scale........................................................................... 157

Table 6.9 Reliability of Subscales and Total Scale for the 30-Item

Self-Efficacy Scale (N=92) .............................................................. 159

Table 6.10 Correlations of the Four Subscales of the 30-Item

Opioid-Taking Self-Efficacy Scale (N=92) ..................................... 160

Table 6.11 Cronbach’s Alpha Values of the Brief Pain Inventory

and the Pain Opioid Analgesics Beliefs Scale (N=92) .................... 160

Table 6.12 Analysis of Skewness and Kurtosis for Variables ........................ 161

Table 6.13 Participants’ Score on the Brief Pain Inventory

(BPI, Short Form) (N=92)................................................................ 162

Table 6.14 Participants’ Pain Relief (N=92)................................................... 163

Table 6.15 Participants’ Score on the Opioid-Taking Self-Efficacy

Scale (N=92) .................................................................................... 164

Table 6.16 Participants’ Score on the Pain Opioid Analgesics

Beliefs Scale (N=92)........................................................................ 167

Table 6.17 Total Daily Oral Morphine Equivalent Conversion Table............ 169

Table 6.18 Adherence Rates for Opioid Analgesics ....................................... 169

Table 6.19 Opioid-Taking Self-Efficacy, Beliefs about Opioid Analgesics,

Analgesic Adherence, and Pain Experience by Gender................... 171

Table 6.20 Opioid-Taking Self-Efficacy, Beliefs about Opioid Analgesics,

Analgesic Adherence, and Pain Experience by Age and Education

.......................................................................................................... 173

Table 6.21 Correlations between Beliefs about Opioid Analgesics,

Opioid-Taking Self-Efficacy, Analgesic Adherence, and

Pain Experience (Pearson’s r)......................................................... 175

Table 6.22 Hierarchical Multiple Regression Analysis for Variables

Predicting Pain Experience .............................................................. 180

Table 6.23 Hierarchical Multiple Regression Analysis for Variable

Predicting Opioid Adherence on an ATC Basis .............................. 183

xii

List of Figures

Figure 3.1 Self-Efficacy Model, Adapted from McDowell, Courtney, Edwards, &

Shortridge-Baggett, 2003 ................................................................ 45

Figure 5.1 Bland-Altman Plots (n=30) to Establish the Agreement between

Test and Retest for Self-Efficacy. The Mean Difference (Solid Line)

and the Limit of Agreement (Broken Lines- 95% Confidence Interval)

Are Indicated................................................................................. 136

Figure 6.1 Scree Plot ....................................................................................... 148

xiii

Statement of Original Authorship

The work contained in this thesis has not been previously submitted to meet

requirements for an award at this or any other higher education institution. To the

best of my knowledge and belief, the thesis contains no material previously

published or written by another person except where due reference is made.

Signature: ____________________

Date: _____________________

xiv

Acknowledgements

I would like to thank my Principal Supervisor Professor Patsy Yates for her advice

and patient guidance during my doctoral studies and, in particular, for her

organizational insight and editorial review. I would also like to thank my Associate

Supervisor Professor Helen Edwards for her insightful comments and criticisms and

substantive opinions throughout this process. I am grateful for the time they devoted

to this project and for providing me with numerous learning opportunities over the

past several years.

Special thanks are extended to Dr. Zandy Clavarino for reviewing this document and

providing her invaluable comments and Professor Mary Courtney for being my panel

member. Appreciation is extended to Professor Christine Miaskowski for the

research measurement advice. Professor Lillie Shortridge-Baggett’s and Dr. Jan

McDowell’s invaluable suggestions and counsel related to instrument development

are deeply appreciated. Special thanks are also given to language and learning

adviser Martin Reese for advice about my academic writing.

I would like to express my thanks to my family for their unceasing support and

encouragement during all my academic endeavours. Their support, encouragement

and love have always been, and will remain, my motivation in life.

Finally, I would like to thank the directors of the oncology department in the two

hospitals for permitting their clinicians to refer their patients for the study. I also

would like to thank all of the subjects who participated in this study. Their

xv

willingness to contribute to improving the care of those experiencing cancer is a

constant source of inspiration for me.

1

Chapter 1: Introduction

1.0 Introduction Pain is a frequent and disturbing symptom of cancer. For many patients it is the most

feared consequence of cancer. Unrelieved pain causes unnecessary suffering.

Effective pain control is associated with an overall increase in quality of life and

should allow patients to have higher levels of function. The purpose of this chapter is

to discuss the background and significance of the study, and to present the aims of

the research. The chapter also briefly describes the research design and methods.

1.1 Background and Significance of the Study 1.1.1 The Prevalence of Cancer Pain

In an advanced stage of cancer, pain is a major symptom for many patients. Surveys

demonstrate that about 30% to 50% of cancer patients, and 70% to 90% of those in

an advanced stage, suffer from chronic pain during active cancer therapy (Foley,

2000; Higginson & Hearn, 1997; Jun, Shujun, & Lijun, 2000; Portenoy & Lesage,

1999; Svendsen et al., 2005; Wells, 2000). A study of 9,105 terminally ill patients

revealed that 50% of conscious patients who died in hospital experienced moderate

to severe pain at least half the time (Connors, 1995). Experts estimate that 80-90% of

cancer pain can be relieved with available methods of pain relief (U. S. Department

of Health and Human Services, 1994; American Pain Society, 2003; Reder, 2001;

World Health Organization, 1996). Several studies have demonstrated that,

unfortunately, these methods are not always used for these patients, leading to

inadequate pain relief (Jun et al., 2000; Moriwaki et al., 2000; Wit, Dam, Vielvoye-

Kerkmeer, Mattern, & Abu-Saad, 1999) and diverse effects on many aspects of

patients’ lives (Jun et al., 2000).

2

1.1.2 Impact of Cancer Pain

Pain is a significant and obvious cause of suffering. Cancer pain not only affects

patients’ physical well-being, but also affects their psychological, social, and

spiritual well-being and thus their quality of life (QOL) (Holtan et al., 2007; Jun et

al., 2000). It can impede functional capability (Thomason et al., 1998), and can result

in disturbed sleep (Avemark, Ericsson, & Ljunggren, 2003; Jun et al., 2000),

decreased activity (Jun et al., 2000), loss of appetite (Avemark et al., 2003),

increased depression, and anxiety (Chen, Chang, & Yeh, 2000; Ferrell, Grant, Funk,

Otis-Green, & Garcia, 1998; Liang & Lin, 1999), and loss of control (Ferrell et al.,

1998). Pain interferes with relationships and roles and with the ability to interact with

loved ones (Ferrell et al., 1998; Keefe et al., 2003). Pain can also create a sense of

uncertainty and hopelessness (Avemark et al., 2003; Ferrell et al., 1998), with

emotional distress being the most consistent psychological variable associated with

pain reports in the cancer population. Furthermore, some researchers (Faller,

Buelzebruck, Drings, & Lang, 1999; Herndon et al., 1999; Mantyh, 2006) have

demonstrated that such emotional distress is significantly associated with shorter

survival times among lung and breast cancer patients, independent of biomedical

prognostic factors. Even when the underlying disease process is stable, uncontrolled

pain prevents patients from working productively, enjoying recreation, or taking

pleasure in their usual roles in the family and society (Jun et al., 2000).

Pain has also been identified as one of the consequences most feared by cancer

patients (Ghooi & Ghooi, 2003; Holtan et al., 2007). Marchettini, Formaglio, and

Lacerenza (2001) have shown that cancer is a very or extremely painful disease, and

that pain is also associated with its treatment. Studies revealed that patients agreed

3

that cancer pain could be a reason for stopping life-prolonging treatment or for

committing suicide (Filiberti et al., 2001; Morita, Sakaguchi, Hirai, Tsuneto, &

Shima, 2004). Moreover, they thought that cancer patients usually die a painful death

(Ghooi & Ghooi, 2003). Unfortunately, poor control of cancer pain appears to be a

problem all over the world (Foley, 2000; Reyes-Gibby et al., 2006; Wells, 2000).

Pain control, therefore, merits a high priority.

1.1.3 Cancer Pain in Taiwan

Cancer has been the leading cause of death in Taiwan since 1982 (Department of

Health, 1983-2005). In the year 2005, cancer amounted to 26.8% of all causes of

death, and the mortality rate from cancer in Taiwan was 163.8 per 100,000 of the

population (Department of Health, 1983-2005). Studies estimate that 31% to 85% of

cancer patients in Taiwan suffer from pain (Chiu, 1997; Ger et al., 1998). For

example, Ger et al. (1998) reported that 38% of cancer patients in Taiwan had

cancer-related pain at the time of admission. Of the patients experiencing pain, 92%

had cancer-related pain, 5% had treatment-related pain, and 3% had both cancer-

related and treatment-related pain. Moreover, 65% to 77% of patients in pain had

“significant worst pain” (worst pain levels at or above five on a ten-point scale) (Ger

et al., 2004; Ger et al., 1998), while 31% had “significant average pain” (average

pain levels at or above five most of the time). Importantly, 54% to 69% of patients in

pain received inadequate medication (not “by the ladder”) (Ger et al., 2004; Ger et al.,

1998) and 23% of patients had pain medication that was not administered at a fixed

interval (not “by the clock”) (Ger et al., 1998). Most patients (69%) in this study,

however, were newly diagnosed (within 14 days) and had just started receiving

4

anticancer therapy. Nevertheless, significant pain can be present for long periods of

time, especially with the development of treatments that prolong life.

1.2 Problem Statement and Significance of this Study Despite the fact that 80-90% of patients could be effectively treated with present

pharmacological therapies and advanced techniques (U. S. Department of Health and

Human Services, 1994; American Pain Society, 2003; Reder, 2001; World Health

Organization, 1996), pain still remains a major source of suffering experienced by

cancer patients (Higginson & Hearn, 1997; Holtan et al., 2007; Jun et al., 2000).

Many deficiencies exist in the treatment of cancer pain (Anderson et al., 2000;

Fazeny et al., 2000; Gunnarsdottir, Donovan, Serlin, Voge, & Ward, 2002; Liu et al.,

2001; Pargeon & Hailey, 1999). The sources of these deficits are multidimensional,

including healthcare provider and patient factors (Anderson et al., 2000; Fazeny et al.,

2000; Gunnarsdottir et al., 2002; Pargeon & Hailey, 1999). The major reasons (35%-

64.4%) for poor management of pain are reported to be patient-related factors

(Ferrell, Eberts, McCaffery, & Grant, 1991; Liu et al., 2001).

Because pharmacological agents are considered to be a cornerstone of cancer pain

management, patients’ adherence to prescribed analgesics is a key to successful

cancer pain control. Consequently, optimal management is dependent on the

patient’s compliance with pain therapies. Evidence suggests that patients, however,

are often reluctant to use pain medication; many patients have misconceptions

regarding analgesics, and do not have enough knowledge about cancer pain and pain

management (Chang, Chang, Chiou, Tsou, & Lin, 2002; Gunnarsdottir et al., 2002;

Yates et al., 2002). Furthermore, many patients have practical difficulties with

adherence to prescribed medications, such as managing constipation in relation to

5

opioid analgesics or accessing medication (Miaskowski et al., 2001; Schumacher,

Koresawa et al., 2002). These factors are likely to effect treatment adherence and to

contribute to inadequate pain relief (Chang et al., 2002; Ersek, Miller Kraybill, & Du

Pen, 1999; Lai et al., 2002; Lin, Chou, Wu, Chang, & Lai, 2006; Thomason et al.,

1998).

Social and behavioural scientists have developed a number of theories and models in

an effort to explain health behaviours such as treatment adherence. These models

include the Health Belief Model (HBM) (Becker, 1974), Theory of Reasoned Action

(TRA) (Fishbein & Ajzen, 1975), and Social-Cognitive Theory (Bandura, 1986).

Such models propose that a person’s belief system crucially influences his or her

behaviour. In the context of pain management these models therefore suggest that

beliefs are one of the key factors contributing to adherence to medication. Moreover

self-efficacy expectations have been proposed in Social Cognitive Theory as a key

factor in understanding health behaviours such as pain management behaviours.

Self-efficacy expectation is defined as a person’s confidence in being able to perform

relevant behaviours in a particular situation (Bandura, 1997). Efficacy beliefs are the

perceived ability to regulate the behaviour effectively and consistently, especially

under difficult circumstances (Bandura, 1997). According to Social Cognitive

Theory (Bandura, 1986), individuals who regard themselves as highly efficacious

with respect to adherence will set higher goals, be more firmly committed to them,

and so exercise greater control over behaviours that foster adherence. Several recent

studies have addressed the role of self-efficacy in the adherence of patients to

exercise (Sweeney, Taylor, & Calin, 2002), diet (Burke, Dunbar-Jacob, Sereika, &

6

Ewart, 2003), and medication (Berg, Dunbar-Jacob, & Sereika, 1997; Gifford et al.,

2000; Johnson et al., 2006; Simoni, Frick, & Huang, 2006). These studies reveal that

self-efficacy beliefs predict adoption and maintenance of exercise behaviours and

weight reduction. Self-efficacy has been shown to correlate positively with

compliance with medications in persons with asthma and HIV/AIDS (Berg et al.,

1997; Gifford et al., 2000; Simoni et al., 2006).

Numerous investigators have begun to examine the relationship of perceived self-

efficacy with the perception of chronic non-malignant pain, and have consistently

shown that perceived self-efficacy is an important determinant of the perception of

chronic pain. For example, perceived self-efficacy is associated with degree of

disability (Barry, Guo, Kerns, Duong, & Reid, 2003), psychological functioning

(Arnstein, Caudill, Mandle, Norris, & Beasley, 1999; Lefebvre et al., 1999; Rahman,

2004), coping behaviour (Lin, 1998a), and medication adherence (Brus, van de Laar,

Taal, Rasker, & Wiegman, 1999; Johnson et al., 2006; Simoni et al., 2006). The

results of these studies suggest that self-efficacy theory may lead to refinements in

understanding of behavioural interventions that may improve both treatment

outcomes and the maintenance of treatment gains (Barry et al., 2003; Brus et al.,

1999; Lefebvre et al., 1999).

Nevertheless, few studies have specifically explored self-efficacy relating to

management of cancer pain. Syrjala and Chapko (1995) focused on a

biopsychosocial model of cancer-treatment-related pain. Their results suggested that

biomedical variables did not fully reflect the sources of cancer-treatment-related pain,

with self-efficacy being a significant predictor of pain for patients. These results

7

emphasise the value of self-efficacy as a construct worthy of evaluation with not only

non-malignant pain, but also cancer pain.

With an increase in outpatient care, patient self-care has become a necessary

component of the cancer experience. Patients are assuming greater responsibility for

cancer pain management at home, so many will have to undertake self-care activities

to control their pain. Many outpatients with cancer will independently regulate their

use of pain medications in response to the complex nature of cancer pain and

incidence of breakthrough pain at home. Because pharmacological agents are

considered to be a cornerstone of cancer pain management, patients’ adherence to

prescribed analgesics has been recognised as the key to successful cancer pain

control. Due to various difficulties (Beck, 1998; Elliott, Elliott, Murray, Braun, &

Johnson, 1996; Miaskowski et al., 2001; Riddell & Fitch, 1997; Schumacher,

Koresawa et al., 2002), however, medication adherence rates amongst patients who

have prescribed analgesics for their cancer pain are lower than what is needed to

achieve optimal pain control (Chang et al., 2002; Du Pen et al., 1999; Lai et al., 2002;

Miaskowski et al., 2001; Zeppetella, 1999).

Active participation in health behaviours can influence outcomes (Punamaki &

Aschan, 1994). Availability of a psychometrically robust instrument to study active

participation as characterised by self-efficacy could assist in efforts to understand the

psychological determinants of health outcomes such as pain. Because self-efficacy is

task-specific, every domain of interest, such as health-related self-care behaviour,

demands a different self-efficacy measure (Berg et al., 1997; Burke et al., 2003;

Simoni et al., 2006; Sweeney et al., 2002). A search of the literature yielded no

8

instrument that measured perceived opioid-taking self-efficacy in cancer patients

with pain. A standardised measure of self-efficacy among cancer patients with pain is

needed.

Studying self-efficacy in cancer patients with pain is important to help health care

professionals to understand the obstacles to cancer pain management. This may

enable the development of more effective strategies for overcoming barriers to

effective treatment of cancer pain.

1.3 Aims 1.3.1 Aims of the Research

The aims of this research were as follows:

1. To develop a scale to measure the self-efficacy expectations in opioid-taking in

Taiwanese outpatients with cancer.

2. To explore how opioid-taking self-efficacy and beliefs about opioid analgesics

contribute to patients’ analgesic adherence and pain experience in Taiwanese

outpatients with cancer.

1.3.2 Research Questions

There were three stages in this study. The research questions for these three stages

were as follows:

Stage One

1. What are the behavioural tasks and situational impediments involved in opioid-

taking self-efficacy in Taiwanese outpatients with cancer pain?

9

Stage Two

1. What is the validity and reliability of the newly developed opioid-taking self-

efficacy scale in Taiwanese outpatients with cancer?

2. Is the self-efficacy scale feasible for use in a cross-sectional survey of Taiwanese

outpatients with cancer?

Stage Three

1. What is the pain experience amongst Taiwanese outpatients with cancer?

2. What is the level of opioid-taking self-efficacy in Taiwanese outpatients with

cancer?

3. What beliefs about opioid analgesics do Taiwanese outpatients with cancer have?

4. What is the adherence rate for analgesics amongst Taiwanese outpatients with

cancer?

5. What is the relationship between opioid-taking self-efficacy, beliefs about opioid

analgesics, adherence behaviours, and pain experience amongst Taiwanese

outpatients with cancer?

6. How much of the variance in pain experience amongst Taiwanese outpatients with

cancer could be accounted for by opioid-taking self-efficacy and beliefs about

opioid analgesics?

7. How much of the variance in analgesic adherence amongst Taiwanese outpatients

with cancer could be accounted for by opioid-taking self-efficacy and beliefs

about opioid analgesics?

1.4 Research Design and Methods This study was divided into three stages. Stage One involved semi-structured

interviews, comprising a series of open-ended questions, to describe the self-efficacy

expectations relating to the behaviours and situational impediments or challenges

10

involved in prescribed opioid-taking amongst Taiwanese outpatients with cancer pain.

In Stage Two, a preliminary test of the validity, reliability, and feasibility of the

opioid-taking self-efficacy scale for this study was undertaken. Stage Three involved

a cross-sectional survey to investigate pain experience, analgesic adherence, beliefs

about opioid analgesics, and opioid-taking self-efficacy, and to determine how self-

efficacy and beliefs about opioid analgesics are related to analgesic adherence and

pain experience. The sampling frame for these three stages was defined as all those

cancer patients with pain who were admitted to the outpatient oncology units of two

teaching hospitals in the Taipei area of Taiwan. Patients were eligible for enrolment

in the study if they met the following inclusion criteria: (1) had a cancer diagnosis; (2)

had an average pain intensity score of ≥ 3 on a 0-10 scale in the past 24 hours; (3)

had been prescribed opioid analgesics for cancer related pain on an around the clock

(ATC) ± as needed (PRN) basis, and had taken them for at least the past week; (4)

was over 18 years of age; (5) was conscious and able to sign the consent form.

For Stage One, data were collected using purposeful sampling. Sampling was ceased

when the researcher failed to obtain new information on the categories/themes from

the participants. This stage began with a pilot study to familiarise the researcher with

the process of conducting an interview and to assess the usefulness of a set of

questions that had been developed for the semi-structured interviews. Scale items

were written based on the themes emerging from the interview data and the literature.

For Stage Two, a convenience sample with 30 eligible subjects was recruited to

examine the face validity and reliability of the initial version of the opioid-taking

self-efficacy scale and to assess the feasibility of the opioid-taking self-efficacy scale

11

for this study. This was done by measuring the time the subjects took to complete

these scales, and asking them their views on the clarity of these questions, and

whether they were easy to answer. The survey was administered to the same 30

cancer patients to calculate test-retest reliability of the self-efficacy questionnaire

after a two-week interval. For Stage Three a cross-sectional survey was administered

to a convenience sample of 92 subjects.

The researcher approached potential subjects who met the inclusion criteria and gave

a brief explanation regarding the purposes and procedures of the study. Consent was

obtained from those who met the criteria and agreed to participate. Depending on

their physical condition and personal preference, the patients responded to the

questions by themselves in writing, or orally to questions read by the researcher. The

researcher collected demographic, disease, and treatment-related data from the

patients’ medical records. The Statistical Package for the Social Sciences (SPSS 13.0)

was used for the quantitative data analysis.

1.5 Overview of the Thesis The thesis consists of seven chapters. Chapter One describes the purpose and

rationale for the study, research questions, background to the problem and its

significance for health outcomes.

Chapter Two presents a conceptual model of pain and multidimensional approaches

to pain management. Pain is characterised as a multidimensional experience

consisting of physiological, sensory, affective, cognitive, behavioural, and

sociocultural components. This chapter discusses the mainstay of cancer pain

control — pharmacological management. This requires a very individual, dynamic,

12

and ongoing approach. In addition, this chapter includes a review of evidence about

the difficulties patients experience with adherence to analgesics. These practical

difficulties may influence patients’ adherence to their prescribed regimen.

Chapter Three provides a review of theoretical and empirical literature on self-

efficacy beliefs. This chapter presents self-efficacy as the beliefs regarded as a

requirement for behaviour change that have an important role in self-regulation. Self-

efficacy beliefs affect the amount of effort devoted to a task, and the length of

persistence when difficulties are encountered. This chapter presents evidence from

various studies that indicate that self-efficacy beliefs have a critical function in health

behaviour and health outcomes, including adherence to medications.

Chapter Four outlines the methodology used in the current study. This chapter

provides a detailed description and justification of the research design and methods

of data collection, which included both quantitative and qualitative components. The

chapter provides details of the sample, the procedures, the measures, and the

processes of data collection and data analysis.

Chapter Five presents findings of the interviews conducted with patients to identify

key aspects of opioid-taking self-efficacy, presenting the major category and themes

that emerged in the context of the patients’ beliefs about their abilities to successfully

perform behaviours or tasks in relation to prescribed opioid taking. This Chapter also

describes the development of the self-efficacy scale and the results of a pilot test to

assess the validity and reliability of the scale and the feasibility of using the self-

efficacy scale.

13

Chapter Six presents the findings from analysis of a cross-sectional survey in

relation to the key research questions in this study. This results chapter includes the

findings from an additional exploratory factor analysis to assess the construct validity

of the new self-efficacy scale.

Chapter Seven is a discussion of the major findings of this study. The results of this

study are reviewed in the light of those from previous studies. The chapter includes

an analysis of important conclusions and implications that can be drawn from the

findings, and suggests how these may be applied to develop improvements in nursing

care and nursing research.

14

Chapter 2: Conceptual Model of Pain and Pain Management

2.0 Introduction Cancer-related pain is a multidimensional experience, consisting of physiological,

sensory, affective, cognitive, behavioural, and sociocultural components. Pain is also

highly subjective and is unique to the individual experiencing it. In this Chapter,

definitions and models of pain and the various factors that influence an individual’s

perception of and response to pain and its pharmacological and non-pharmacological

management are presented.

2.1 Definition of Pain Although a number of authors have proposed definitions of pain, a widely accepted

definition is that of the International Association for the Study of Pain [IASP] (1986),

which states that pain is “an unpleasant sensory and emotional experience associated

with actual or potential tissue damage, or described in terms of such damage” (p.217).

This definition encompasses not only pain of pathophysiological origin but also the

psychological dimension of the pain experience. McCaffery’s often-cited definition

emphasises the subjective dimension of pain, when she writes that pain is “whatever

the experiencing person says it is, existing whenever he or she says it does” (p.2)

(McCaffery, 2000). This subjective nature of the pain experience presents some

important challenges for its assessment, measurement, and management. In particular,

these definitions reveal that the type and extent of disease may not be the only factor

influencing an individual’s report of pain.

15

2.2 Multidimensional Components of Pain The concepts of the Gate Control Theory of Pain were the first to emphasise the

different aspects of pain perception and integrate the physiological, psychological,

and cognitive components involved in the experience of pain (Melzack & Wall, 1965;

Melzack & Wall, 1996). The theory emphasised that pain has multidimensional

components. The neuromatrix theory of pain was proposed as an expansion of the

Gate Control Theory (Melzack & Wall, 1996) to understand brain functions as a

neural network and provide an understanding of the multidimensional phenomenon

of pain (Melzack, 1999; Melzack & Wall, 1996). The expanded theory of Melzack

(1999) integrated pain and other stressors and identified the relationship between

pain sensitivity and homeostatic physiological activities. A body self neuromatrix

that can influence pain sensitivity to maintain homeostatic equilibrium was proposed.

He suggested that this neurosignature pattern is modulated by three dimensions of

pain experience and behaviour. Ahles, Blanchad and Rucksdeschel (1983) similarly

built on the Gate Control Theory to describe a multidimensional conceptualisation of

cancer-related pain, dividing the pain experiences of patients into five components:

physiologic, sensory, affective, cognitive, and behavioural. McGuire (1995) added

the sociocultural dimension to the personal experience of pain. This

conceptualisation of cancer-related pain provides a useful framework to understand

the factors that may affect an individual’s perception and interpretation of pain.

Common to all contemporary models of pain is acknowledgement of the

multidimensional nature of this experience. In the following section, these various

components of the pain experience will be described; while they are presented

separately for the purpose of description the complex interrelationships between the

components need to be acknowledged.

16

2.2.1 Physiological Component of Pain

The physiological component of cancer-related pain encompasses the underlying

pathological basis of the pain. The pathophysiology of pain in cancer is complex.

Cancer pain can be classified according to aetiology. Several studies have grouped

cancer pain into three categories: (1) pain associated with cancer as a direct result of

tumour growth (invasion of bone or neural structures is the most common cause)

(Banning, Sjogren, & Henriksen, 1991a; Portenoy & Hagen, 1990); (2) pain as a

consequence of antineoplastic therapy (Banning et al., 1991a); and (3) pain in cancer

patients that is unrelated to their cancer (Banning et al., 1991a). Patients often

present with multiple pains, many of which can have a combination of different

causes (McGuire, 1991; Portenoy & Lesage, 1999).

Cancer pain can also be divided into three classes: somatic, visceral, and

deafferentation pain (American Cancer Society, 2001; Portenoy & Hagen, 1990).

Somatic pain results from activation of nociceptors in cutaneous and deep tissues,

such as bone or muscle (Kanner, 1993; Kelly & Payne, 1991). This pain is typically

well localized and is usually constant (Kanner, 1993). Visceral pains are related to a

lesion in a hollow or solid viscus, resulting from stretching or distending (Procacci &

Maresca, 1990). It is typically poorly localized and commonly referred to

subcutaneous sites (Patt, 1993). Deafferentation pain refers to a lesion of the

peripheral and/or central nervous system, from tumour compression or infiltration of

peripheral nerves or the spinal cord (Cherny & Foley, 1994). Also it can be caused

by injury to peripheral nerves as a consequence of surgery, chemotherapy, or

radiation therapy for cancer. Most patients with advanced cancer have multiple pains

17

due to different pathologies (Banning et al., 1991a; Dicks, 1990; Twycross, Harcourt,

& Bergl, 1996).

2.2.2 Sensory Component of Pain

The sensory component of cancer pain is experienced in terms of its perceived

quality and intensity. The quality of pain may vary according to the underlying cause

or aetiology. For example, somatic pains are frequently described as aching, or

gnawing (Kanner, 1993). Visceral pains result from stretching or distending

(Procacci & Maresca, 1990); their character is described as deep, squeezing, and as

pressure. Deafferentation pains are typically described as constant, burning, tight, or

lancinating (Kanner, 1993).

Pain intensity is the most commonly assessed aspect of pain. Intensity is an

extremely subjective phenomenon that may or not be related to the underlying

pathophysiology. As suggested by the multidimensional model of pain, pain intensity

can be affected by many factors including medication, as well as emotional and

cognitive factors (Ahles et al., 1983; Arnstein et al., 1999; Lefebvre et al., 1999).

In addition to constant background pain, many cancer patients frequently experience

breakthrough pain. Breakthrough pain has been defined as a transitory increase in

pain intensity on a baseline of moderate intensity in patients on regularly

administered analgesic treatment (Mercadante, Radbruch et al., 2002). It is

characterised as spontaneous, occurring either without an identifiable precipitating

event, or precipitated. In various surveys, 40-90% of cancer patients with pain have

been reported to experience breakthrough pain (Banning, Sjogren, & Henriksen,

18

1991b; Davis, Walsh, Lagman, & LeGrand, 2005; Fine & Busch, 1998; Portenoy &

Hagen, 1990). Breakthrough pain has been recognised as a challenging pain

phenomenon in cancer.

2.2.3 Affective Component of Pain

The affective component of the pain experience encompasses the subjective

unpleasant feeling of pain and the emotional disturbances or negative moods

associated with pain, for example, anxiety, depression, and anger (Glover, Dibble,

Dodd, & Miaskowski, 1995; Portenoy, Payne, & Jacobsen, 1999; Speigel, Sands, &

Koopman, 1994; Zimmerman, Story, Gaston-Johansson, & Rowles, 1996).

According to Chapman (1995), emotion is a fundamental part of the pain experience.

The International Association for Study of Pain similarly states that pain “is

unquestionably a sensation in a part or parts of the body, but it is also always

unpleasant and therefore also an emotional experience” (p.250) (Merskey, Albe-

Fessard, & Bonica, 1979). Conceptually, unpleasant emotional symptoms often occur

concurrently with the pain sensation, which may trigger further emotional distress.

As suggested by this multidimensional conceptualisation of pain, these emotional

responses to pain may be affected not only by pain intensity, but also by cognitive

processes. For example, studies reveal that patients reporting higher levels of self-

efficacy have lower levels of pain as well as lower levels of psychological distress

(Arnstein et al., 1999; Lefebvre et al., 1999).

2.2.4 Cognitive Component of Pain

The cognitive component of the pain experience relates to the processes by which

pain influences the individual’s thoughts and the way in which they perceive,

19

interpret, and relate to their pain, for example, attitudes toward pain, reporting pain,

pain medication, and specific self-efficacy beliefs (Wit, Dam, Litjens, & Abu-Saad,

2001). Beliefs about pain (Lai et al., 2003; Sherwood, Adams-McNeill, Starck, Nieto,

& Thompson, 2000), pain medication (Coward & Wilkie, 2000; Gunnarsdottir et al.,

2002), and beliefs about ability to control pain (Asghari & Nicholas, 2001) are

suggested also to be related to other key behavioural constructs, such as compliance

with treatment.

Patients’ knowledge and beliefs about pain are critical components in pain

management (Beck, 1998; Lai et al., 2003). Lack of knowledge or misconceptions

regarding pain may lead to poor symptom management. Patients frequently possess

negative beliefs regarding cancer pain. For example, the idea that cancer pain is an

inevitable part of the disease process (Levin, Cleeland, & Dar, 1985; Taylor &

Crisler, 1988), pain can not be relieved (Levin et al., 1985; Riddell & Fitch, 1997),

pain indicates a deteriorating condition (Ahles et al., 1983; Cleeland, 1989), when

cancer pain persists and worsens it is an indicator of progressive disease (Lin &

Ward, 1995; Moore, 1999; Ward, Goldberg, Miller-McCauley, & Mueller, 1993;

Ward & Hernandez, 1994) and an adult should endure as much pain as possible (Lai

et al., 2003), are common misconceptions. In addition, some patients believe the pain

serves as a warning to protect the part that hurts and they might overdo it if they were

too comfortable (Coward & Wilkie, 2000; Gunnarsdottir et al., 2002). These beliefs

may affect patients’ expectation about cancer pain management and the effect of

analgesics, and therefore, effect patients’ willingness to take analgesics for managing

their pain (Gunnarsdottir et al., 2002; Lai et al., 2002).

20

Many patients are reluctant to report pain due to various thoughts; however, without

the patients’ detailed reporting, accurate pain assessment is impossible. Concerns of

patients that may influence their beliefs about reporting pain include their concern

about not being a “good” patient, if they complain about their pain to clinicians. In

addition, patients may be concerned about distracting their physician from treating of

underlying disease (Lin & Ward, 1995; Ward et al., 1993; Ward & Hernandez, 1994).

Furthermore they may also fear a negative response from clinicians when they

request narcotic analgesics (Tucker, 1990) and are concerned about clinician’s

hesitancy to give medications because of fears of addiction (Ferrell, Rhiner, Cohen,

& Grant, 1991). These considerations may limit their willingness to report pain and

access to analgesics, thus resulting in unrelieved pain.

Other studies have demonstrated that many patients are concerned about the use of

pain medication. The concerns include concern about addiction, tolerance, and side

effects (Coward & Wilkie, 2000; Gunnarsdottir et al., 2002; Paice, Toy, & Shott,

1998; Riddell & Fitch, 1997). The Word Health Organization (1996) has consistently

reported that the likelihood of addiction occurring from use of opioids for pain relief

is very small,

21

(Paice et al., 1998). Experts have suggested that concern about tolerance should

never prevent the early use of analgesics for patients with cancer pain (Portenoy,

1993).

Concern about side effects deserves particular attention. Previous or ongoing

experiences with analgesic side effects can limit patients’ willingness to follow

prescribed treatment for pain management (Coward & Wilkie, 2000; Gunnarsdottir et

al., 2002). Many participants tended to hold back on medication, because they were

concerned about side effects such as nausea, constipation, and potential liver damage

(Coward & Wilkie, 2000; Gunnarsdottir et al., 2002). In addition, the unpleasant

experiences of drowsiness and mental confusion may cause patients to be unwilling

to take pain medications (Coward & Wilkie, 2000; Gunnarsdottir et al., 2002). This

is despite the fact that many analgesic side effects can be prevented from occurring

and others can be effectively managed with existing strategies (McNicol et al., 2003).

Patients still hold the belief that side effects of analgesics are inevitable and

unmanageable (Gunnarsdottir et al., 2002).

Other beliefs about pain medications such as that pills may do more harm than

suffering some pain (Coward & Wilkie, 2000) and pain medications were “bad” for

their body (Riddell & Fitch, 1997) may influence patients to be reluctant to take pain

medications regularly or to take sufficient doses for adequate pain relief.

Patients’ negative beliefs regarding cancer pain and pain management, reporting their

pain, and their concerns about use of analgesics are likely to influence patients’

analgesic-taking behaviour. However, for reasons that are not fully understood, some

22

patients continue to have difficulty adhering to pain management regimens even after

educational interventions in relation to knowledge and beliefs about pain

management (Wells, Hepworth, Murphy, Wujcik, & Johnson, 2003; Yates, Edwards

et al., 2004).

Although pain management education results in improved pain control for some

patients, it does not enable all patients to change their behaviour (Schumacher,

Koresawa et al., 2002; Ward, Donovan, Owen, Grosen, & Serlin, 2000) or achieve

reduction in pain (Ward et al., 2000; Yates, Edwards et al., 2004). In turn,

improvements in patients’ knowledge and attitudes do not necessarily result in

behaviour change. This may reflect the difficulties of applying this knowledge to a

practical situation (Schumacher, Koresawa et al., 2002) and underscores the

importance of understanding the multiple dimensions of pain. Clearly a full

understanding of the complex and multidimensional nature of pain and pain

management and the relationship between pain dimensions such as belief and

behaviour is a priority (Du Pen et al., 1999).

2.2.5 Behavioural Component of Pain

The behavioural component of pain includes a variety of behaviours related to

responses to pain, such as self-reporting of pain, or the abilities and behaviours

related to use of pharmacological methods to treat pain (Kimberlin, Brushwood,

Allen, Radson, & Wilson, 2004; Lin, 1998b). When patients make conscious

decisions to engage in some of these behaviours, they make cognitive decisions. But

the actual use of these techniques lies within the behavioural dimension (McGuire,

1995). The notion highlights the importance of cognitive and behavioural

23

dimensions of cancer pain management. For example, the concept of self-efficacy

beliefs has been used to explain many of the behaviours and disabilities of people in

chronic non-cancer pain (Barry et al., 2003; Brus et al., 1999; Lefebvre et al., 1999),

but has received less attention in the cancer pain literature.

Around 80-90% of cancer patients could be kept free from cancer pain by following

the pharmacological guidelines of the Agency of Health Care Policy and Research

(AHCPR)(U.S. Department of Health and Human Services, 1994; American Pain

Society, 2003; Reder, 2001; World Health Organization, 1996). Patients’ adherence

behaviour is therefore important in effective pain control.

There is however, wide variation in adherence to prescribed analgesics. Studies

report adherence levels ranging from 16% to 90% in patients with cancer-related

pain (Chang et al., 2002; Du Pen et al., 1999; Lai et al., 2002; Miaskowski et al.,

2001; Zeppetella, 1999). Overall adherence rates are reported to be around 22% to

27% when patients use the analgesics prescribed on an as-needed basis (Miaskowski

et al., 2001).

Another important behavioural response to pain is communication about pain and

pain management. Studies suggest patients’ negative beliefs about analgesics affects

their reluctance to report pain and to use analgesics (Kimberlin et al., 2004; Lai et al.,

2002).

Studies also suggest that patients have difficulties overcoming various practical

impediments to engaging in effective behavioural responses to pain, such as

24

accessing information, managing side effects, or tailoring prescribed regimens to

meet individual needs (Schumacher, Koresawa et al., 2002). Bandura asserted that

self-efficacy beliefs are a critical element that contribute to health behaviours such as

medication adherence. Self-efficacy reflects the belief in one’s confidence in his or

her ability to overcome various difficult situations in order to perform a specific

behaviour. For example, according to Bandura, one’s confidence in his or her ability

to overcome various difficult situations in performing a behaviour is an important

bridge between knowing what to do and actually doing it. Besides knowing what to

do, he or she must know how to do it and want to do it (Bandura, 1977a; Lawrance &

McLeroy, 1986). These notions emphasize the crucial link between practical

difficulties of taking analgesics and beliefs related to one’s confidence in his or her

ability to overcome these difficulties. These associations further underscore the

multidimensional nature of pain experiences, and the complex association between

cognitive and behavioural aspects of pain. Few studies however, focus on self-

efficacy beliefs associated with cancer pain management.

2.2.6 Sociocultural Component of Pain

The sociocultural component of pain includes demographic, ethnic, cultural and

other factors, such as social support, that may influence perception of and response to

pain (Cleeland, Gonin, Baez, Loehrer, & Pandya, 1997; Fillingim & Maixner, 1995;

Thomason et al., 1998; Unruh, 1996). For example, sociocultural factors can

influence an individual’s beliefs about pain and adjustment to the total pain

experience. As Morris (1999) stated “no one experiences pain free from human

mediation, including the mediation of our own experiences” (p. 118). This notion

implies that an individual’s pain experience bears the imprint of social structures,

25

such as family or hospital, and of cultural environments such as religion, ethnic

group, or nationality that necessarily shape and influence pain.

Based on the neuromatrix theory of pain, cognitive processes involving emotional,

sociocultural, and experiential factors influence the pain process. That is, when a

noxious event occurs, the individual’s past memories and cultural beliefs may

influence whether pain impulses reach the levels of awareness, and may significantly

influence the perception of pain and the response to pain (Barkwell, 2005; Cohen,

Musgrave, Munsell, Mendoza, & Gips, 2005). For example, cultural patterning and

interpersonal relationships among people in the same culture may teach a person

whether pain is to be ignored or accepted, or whether or not certain reactions to pain

will receive approval. Culture similarly has an important influence on illness beliefs

and health care utilization, help-seeking activities, and receptivity to medical care

interventions (Juarez, Ferrell, & Borneman, 1999; Lasch et al., 2000; Moore &

Spiegel, 2000).

Although research has shown no racial or ethnic differences in sensory threshold

(Ramer, Richardson, Cohen, & Bedney, 1999), some studies (Cleeland et al., 1997;

Vallerand, Hasenau, Templin, & Collins-Bohler, 2005) indicate that pain tolerance

reflects attitudinal and behavioural aspects of pain that may be culturally determined.

These studies suggest culture has a significant impact on pain perception and pain

responses, including the use of specific coping strategies (Cleeland et al., 1997;

Juarez, Ferrell, & Booneman, 1998; Lin, 1998a). For example, Juarez et al. (1998)

found that in Hispanic cancer patients, the suppressed verbal or behavioural

26

expression of pain does not indicate less pain, but rather the influence of culture,

family beliefs, and religion on pain responses.

Based on a Chinese cultural attribute, the teaching of Taoism, Chinese patients

perceive cancer as an incurable disease; they accept pain as their fate, part of their

life, and a reminder of life (Chung, Wong, & Yang, 2000). In addition, due to the

abuse of opium in China in the nineteenth century, the Chinese government has a

very stringent policy toward any opioids, thus giving the impression that opioids are

bad. Beliefs that it is wrong to take opioids and that one can easily become addicted

to opioids are deeply rooted in Chinese people’s minds (Ger, Ho, & Wang, 2000).

Many cancer patients in Taiwan are, like Western patients, dealing with and

suffering from pain (Chang et al., 2002; Lai et al., 2003; Lai et al., 2002). These

problems may be highly influenced by the social and cultural context.

2.3 Multidimensional Approaches to Pain Management The pain experience is multidimensional and must be viewed as an interrelated and

interactive whole. For example, as illustrated by the multidimensional model of pain,

pain (sensory component) may lead to psychological distress (affective component),

which in turn may exacerbate the pain (sensory component) (Liang & Lin, 1999). In

addition, patients’ perceptions of their capability to control their pain (cognitive

component) may influence their adherence behaviour relevant to their

pharmacological regimen (behavioural component) and therefore influence their pain

intensity (sensory component) or psychological distress (affective component) or

other outcomes of pain control.

27

To modify responses to multidimensional phenomenon of pain, a range of strategies

has been considered for managing cancer pain, including pharmacological and non-

pharmacological methods (U. S. Department of Health and Human Services, 1994).

Non-pharmacological methods such as relaxation can enable patients to gain a sense

of control and improve their coping skills. Many non-medicinal complementary

therapies have been shown to help the patient with cancer. Strategies such as

relaxation/imagery (Anderson et al., 2004; Kwekkeboom, Kneip, & Pearson, 2003;

Wallace, 1997), distraction (Anderson et al., 2004), transcutaneous electrical nerve

stimulation (TENS) (Chiarini et al., 1997; Hidderley & Weinel, 1997), acupuncture

(Alimi et al., 2003; He, Friedrich, & Ertan, 1999; Mao-Ying et al., 2006), hypnosis

(Richardson, Smith, McCall, & Pilkington, 2006), massage (Calenda, 2006; Wilkie,

2000), or herbal medicine (Kalant, 2001; Martin & Willey, 2004) have been shown

to be effective in improving pain outcomes. Nonpharmacological methods are

especially targeted at the cognitive, affective and behavioural components of pain.

For example, cognitive behavioural pain relief strategies such as guided imagery may

help patients cope with the meaning of their pain (cognitive component) and

decrease feelings of distress and hopelessness (affective component), thereby

resulting in pain relief (sensory component). In cancer pain control such

nonpharmacological measures are thus an important adjunct to pharmacological

approaches for cancer pain management (U.S. Department of Health and Human

Services, 1994).

Pharmacological therapy is the cornerstone of cancer pain management. For effective

pharmacological treatment of cancer pain, agreement exists on the principles of

pharmacological management by several institutes, such as the World Health

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Organization [WHO] (1996), American Pain Society (2003), and Agency for

Healthcare Policy and Research [AHCPR] (U.S. Department of Health and Human

Services, 1994). The appropriate application of pain management regimens relies on

initiating therapy, titrating dose, scheduling around the clock (ATC), and

preventing/minimizing side effects. These standards guide the appropriate

application of pharmacological management of cancer pain.

Essential components of analgesic therapy include administering it following the

WHO ‘ladder’ regimen (World Health Organization, 1996). The WHO 3-step ladder

of analgesic therapy is as follows: Step 1: non-steroidal anti-inflammatory drugs

(NSAIDs); Step 2: weak opioid analgesics; Step 3: strong opioids, with (a) ± co-

analgesics (adjuvants) at every step, (b) titrating drug dose to effect, (c) dosing

around the clock (ATC), (d) using the oral route when possible, and (e) preventing

and aggressively treating analgesic side effects. These pharmacological principles are

also endorsed by the American Pain Society (American Pain Society, 2003) and the

Agency for Health Care Policy and Research (U.S. Department of Health & Human

Services, 1994).

The goal of chronic cancer pain management is not only pain relief but also pain

prevention (Mercadante, Villari, Ferrera, & Casuccio, 2004). Therefore, prescribing

guidelines emphasise titrating the dose to effectiveness and then taking around the

clock doses (ATC) at regularly scheduled intervals, rather than on the more common

“as needed” basis (World Health Organization, 1996). The advantages of ATC

therapy and oral medication are some of the motivations for the development of

controlled-release, oral formulations of opioids (Reder, 2001). The reduced dosing

29

frequency makes the oral medication more convenient for patients, making it easier

for them to comply with the dosing regimen, assuming analgesic use will become a

routine behaviour. The exception to this is the recommended practice of having

“breakthrough” medication available. Cancer patients with pain often routinely take

one analgesic ATC and then learn to take another medication as needed (PRN) for

extra pain. Guidelines also emphasise how to treat a number of side effects, including

constipation, nausea, vomiting, sedation, mental clouding, respiratory depression, dry

mouth, and sleep disturbances (U.S. Department of Health and Human Services,

1994).

Studies show that skilled practitioners can adequately relieve upwards of 80-90% of

patients from suffering cancer pain when treatment follows the recommended

guidelines for pain management (Levy, 1994; Portenoy, 1993; Schug, Zech, & Dorr,

1990; World Health Organization, 1996). Nevertheless, the variable and complex

nature of cancer pain, the incidence of breakthrough pain and the side effects of

analgesics, mean that there are many factors that can reduce the likelihood of

adequate pain control (Mercadante, Fulfaro, & Casuccio, 2002; Mercadante et al.,

2004; Portenoy et al., 1999; Zeppetella, O'Doherty, & Collins, 2000). In particular,

the complex, variable and subjective nature of pain mean that patients need to tailor

their medication regimens by problem-solving around individual responses to the

medications and progressively modifying their regimen as needs change, for example

in response to breakthrough pain at home. Tailoring a prescribed regimen to meet

individual needs is a complex, dynamic, and ongoing effort (Schumacher, Koresawa

et al., 2002). While such prescribing decisions are clinically based, patients are

involved in decision-making for this tailoring process, as they need to be able to

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interpret pain experiences, communicate these and respond appropriately; so their

adherence to prescribed pain therapies may be affected (Chang et al., 2002; Du Pen

et al., 1999; Lai et al., 2002; Miaskowski et al., 2001; Zeppetella, 1999). Such

findings again underscore the importance of multidimensional models of pain, and

developing a better understanding of the nature of the relationships between the

various dimensions.

2.4 Evidence Review on Difficulties with Patients’ Adherence to Pharmacological Therapies

2.4.1 The Concepts of Adherence

A number of terms are commonly used with respect to medication-taking, including

“compliance” and “adherence” (Steiner & Earnest, 2000; Vlasnik, Aliotta, & DeLor,

2005). Some researchers suggest, however, that these terms subtly overstate the

importance of the clinician and may not accurately represent patients’ motivations

for choosing to take their medications in a certain way (Bissell, May, & Noyce, 2004;

Steiner & Earnest, 2000). Other researchers have thus described models such as the

“self-medication hypothesis” (Mitchell, 2007) or the “concordance model” (Bissell et

al., 2004) to reflect patient perspectives in the context of prescribed medication.

More specifically, some writers argue that “compliance” implies a submissive

behaviour of complying with a provider’s “will and order” (Vlasnik et al., 2005).

Others prefer the contrasting term “adherence” (Osterberg & Blaschke, 2005;

Vlasnik et al., 2005), as this is seen to be a more patient-centred term. It is argued

that such terms better reflect reality, that patients carry out and maintain certain

behaviours, such as taking medications, after making an informed choice in a

31

supportive environment (Vlasnik et al., 2005). Adherence thus implies the patient has

autonomy in choosing to follow a health care regimen (Evangelista, 1999). The term

implies that patients are active participants in their own health care, with control over

health care decisions. The concept of adherence further implies that the patient does

not passively conform to health care advice (Evang