Collins, BJ April 2016

328 Pages·2016·6.1 MB·English

by  Brendan Collins

Collins, B.J.
April 2016
Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness

Thesis submitted in accordance with the requirements of the

University of Liverpool for the degree of Doctor in Philosophy

1 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness

Thesis submitted in accordance with the requirements of the
University of Liverpool for the degree of Doctor in Philosophy by
Brendan Joseph Collins

January 2016

Supervisors: Dr Alan Haycox
Dr Mike Rowe

2 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
Applying Economic Evaluation to Public
Health: Case Studies in Cost Effectiveness
Brendan Collins
Abstract
For local public health teams, commissioning services that work and are cost effective is
important. Having ways of evaluating and assessing their cost effectiveness is invaluable.
Health economics and public health have a natural kinship as they both take a population
approach to maximising health. The aim of this investigation is to give examples of how a
mixed methods approach can be used. This thesis gives three case studies where public
health commissioned services for alcohol, tobacco and drug addiction in the North West of
England have been evaluated for their cost effectiveness using a mix of economic evaluation
techniques combined with elements of realist evaluation and equity impact analysis. These
mixed methods evaluation techniques involve engaging with stakeholders to develop a
common understanding of outcomes and assumptions in reaching a common understanding
of the causal mechanisms that make an intervention work. This thesis outlines how the
results of these evaluations were useful in informing strategy and the commissioning
process and how they may be used more in the future. There were some novel analyses
including matching up crime data and putting a cost on these crimes for people in contact
with a drugs test on arrest programme, which found that costs were lower after the drug
intervention. The researcher found that there was not a significant change in admissions
post-detoxification which indicates that perhaps inpatient residential detoxification has only a
limited effect on long term health prospects. This thesis has shown that economic evaluation
and realist evaluation methods pose some challenges but can be carried out at a local level
as a way of looking at public health interventions through a more complex lens.

3 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
Table of Contents
Abstract................................................................................................................................. 3
Table of Contents .................................................................................................................. 4
Acknowledgements ............................................................................................................... 8
List of Figures ....................................................................................................................... 9
List of Tables ...................................................................................................................... 13
List of Acronyms ................................................................................................................. 17
Chapter 1. Introduction ........................................................................................................ 22
1.1 Why Choose This Topic? ........................................................................................... 22
1.2 A Pen Portrait of Wirral - A Microcosm of the UK? ..................................................... 24
1.3 Structure of the Thesis ............................................................................................... 29
Chapter 2. History of Public Health & Addiction Research .................................................. 31
2.1 What is Public Health? ............................................................................................... 31
2.2 A Recent History of Public Health in the UK .............................................................. 33
2.3 Summary of Theories of Health Inequalities .............................................................. 36
2.4 History of Addiction Theories ..................................................................................... 39
2.5 Criticism of Addiction Theories .................................................................................. 42
2.6 Summary of Addiction Theories ................................................................................. 44
2.7 The Structure of Public Health in the UK.................................................................... 44
Chapter 3. History and Application of Health Economics ..................................................... 49
3.1 The Background to Health Economics ....................................................................... 49
3.2 Allocative and Technical Efficiency ............................................................................ 50
3.3 Egalitarianism vs. Utilitarianism ................................................................................. 51
3.4 Welfarism and Extra-Welfarism ................................................................................. 52
3.5 Health Economic Approaches and Methodologies ..................................................... 53
3.5.1 Main Methods ..................................................................................................... 53
3.5.2 Social Return on Investment (SROI) ................................................................... 55
3.5.3 Multi-Criteria Decision Analysis (MCDA) ............................................................. 56
4 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
3.5.4 Economic Modelling ............................................................................................ 57
3.6 Applying Health Economics to Public Health Interventions ........................................ 62
3.7 NICE and Public Health ............................................................................................. 63
3.8 Case Studies of Public Health Cost Effectiveness ..................................................... 65
Chapter 4. Theoretical Basis of Work .................................................................................. 70
4.1 Objectives of Work .................................................................................................... 70
4.2 What do we mean by 'Evaluation'? ............................................................................ 70
4.3 Policy & Implementation ............................................................................................ 73
4.4 The Evaluation Problem – Dealing with Complexity - Realist Evaluation ................... 79
4.5 The Realist Evaluation Process ................................................................................. 86
4.6 Summary – Introductory Chapters ............................................................................. 87
Chapter 5. Economic Evaluation of Smoking Services ........................................................ 90
5.1 Smoking - Burden of Disease .................................................................................... 90
Smoking prevalence .................................................................................................... 92
Cannabis...................................................................................................................... 95
Electronic cigarettes ..................................................................................................... 96
Smoking in Pregnancy ................................................................................................. 96
5.2 Smoking - Available Interventions .............................................................................. 98
5.3 Background to Case Study ...................................................................................... 100
5.4 Cost Effectiveness of Smoking Services - Case Study ............................................ 101
5.4.1 Aim.................................................................................................................... 101
5.4.2 Literature review................................................................................................ 101
5.4.3 Data sources ..................................................................................................... 102
5.4.4 Methods ............................................................................................................ 104
5.4.5 Results .............................................................................................................. 108
5.4.6 Discussion......................................................................................................... 126
5.4.7 Conclusion ........................................................................................................ 129
Chapter 6. Economic Evaluation of Alcohol Treatment Services ....................................... 130
6.1 Alcohol - Burden of Disease .................................................................................... 130
5 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
6.2 Alcohol – Available Interventions ............................................................................. 138
6.3 Background to Case Study ...................................................................................... 142
6.4 Case Study .............................................................................................................. 146
6.4.1 Aim.................................................................................................................... 146
6.4.2 Literature review................................................................................................ 146
6.4.3 Data sources ..................................................................................................... 149
6.4.5 Methods ............................................................................................................ 149
6.4.6 Results .............................................................................................................. 154
6.4.7 Discussion ................................................................................................... 170
6.4.8 Conclusion ........................................................................................................ 171
Chapter 7. Economic Evaluation of Drug Treatment Services ........................................... 173
7.1 Drugs - Burden of Disease ...................................................................................... 173
Local Data on Drugs and Crime ................................................................................. 187
7.2 Drug Treatment – Available Interventions ................................................................ 190
7.3 Background to Case Study ...................................................................................... 201
7.4 Case Study .............................................................................................................. 207
7.4.1 Aim.................................................................................................................... 207
7.4.2 Literature review................................................................................................ 208
7.4.3 Data sources ..................................................................................................... 213
7.4.4 Methods ............................................................................................................ 213
7.4.5 Results .............................................................................................................. 220
7.4.6 Discussion......................................................................................................... 246
7.4.7 Conclusion ........................................................................................................ 253
Chapter 8. Discussion ....................................................................................................... 254
8.1 What this Thesis adds to the Canon of Knowledge .................................................. 254
Implementation .......................................................................................................... 254
8.2 Policy Recommendations ........................................................................................ 257
8.3 Limitations of this Research ..................................................................................... 260
8.4 Recommendations for Future Research & Methods ................................................ 261
6 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
8.5 Reflections on Research .......................................................................................... 265
8.5.1 Overall Reflections ............................................................................................ 265
8.5.2 QALYs .............................................................................................................. 266
8.5.3 Modelling .......................................................................................................... 267
8.5.4 Realist Evaluation ............................................................................................. 268
8.6 Conclusions ............................................................................................................. 270
References ....................................................................................................................... 271
Appendix 1. Poster presented at University poster day, 2014. .......................................... 292
Appendix 2. Semi Structured Interview Questions. ............................................................ 293
Questions for semi structured interview for specialist smoking cessation treatment. .. 293
Questions for semi structured interview for alcohol specialist treatment. .................... 293
Questions for semi structured interview for drug treatment. ....................................... 294
Appendix 3. Brief Report; Using a Survey to Estimate Health Expectancy and Quality
Adjusted Life Expectancy to Assess Inequalities in Health and Quality of Life. ................. 295
Appendix 4. Smoking Treatment Data Definitions ............................................................. 304
Appendix 5. Drug & Alcohol Treatment Data Definitions ................................................... 305

7 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
Acknowledgements
I am grateful to everyone for their assistance. However, the work is my own and I am
responsible for the content of this thesis.
A big thank you goes to Alan Haycox, my supervisor and mentor at the University and to
Mike Rowe my second supervisor. And thank you to my examiners, Sarah Louisa Phythian-
Adams, Harry Sumnall, and Louis Niessen. Also everyone at Wirral Council who have
funded my job and helped me with my work, in particular Fiona Johnstone the Director of
Public Health, and Julie Webster the Head of Public Health, Bev Murray, Tony Kinsella who
has supervised me day to day and who coaxed me back up to Merseyside from London, and
Chris Harwood who has taught me so much over the years, and everyone in the
Performance and Public Health Intelligence Team and the public health commissioners and
providers. Also the service leads, Kim Ozano, Rebecca Mellor, Gary Rickwood and Bev
Dajani and all of the service providers and users. Thank you to Kevin Cuddy who I worked
with on the DIP analysis. Also to thank my family, my mum, my dad who studied at Liverpool
for a long time, and 4 out of my 5 brothers and sisters who also did their undergrads (and my
brother Chris his MSc) here at Liverpool, between us all we must have clocked up a good
quarter of a century here.
This thesis is partly the story of me. My mother's parents were both brain doctors (a
psychiatrist and a neurologist) who lit my interest in the brain. I grew up in an area of deep
deprivation which sparked my interest in health inequalities before I knew what health
inequalities were. The first time I learned about psychology it explained so much to me, and
the first time I learned about health economics it really chimed with my ideas about human
behaviour and preferences. I think that health economics as a discipline has its limitations
but is very explicit about it, and maybe apologises too much. More recently when I learned
more about realist evaluation it really spoke to me as a way of accounting for complexity and
thinking about the mechanism; previously for any evaluation my first question would be
describe the mechanism; because to me this is the way of proving that you know how your
service is achieving its outcomes.
This thesis is dedicated to my wife Sarah and my son Thomas.

8 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
List of Figures
Figure 1. Map showing national IMD (Index of Multiple Deprivation) 2010 ranking of LSOAs
(lower layer super output areas in Wirral, with wards overlayed. ......................................... 25
Figure 2. Deprivation against smoking in Wirral. ................................................................. 26
Figure 3. Deprivation against binge drinking in Wirral. ......................................................... 26
Figure 4. Deprivation against obesity in Wirral. ................................................................... 27
Figure 5. Deprivation against eating 5 or more fruit and veg a day in Wirral. ....................... 27
Figure 6. Global DALYs (Disability Adjusted Life Years) Lost Due to Different Risk Factors.
Source: WHO (2009). .......................................................................................................... 33
Figure 7. The COM-B Behaviour Change Wheel. ................................................................ 42
Figure 8. Example of a decision tree for a clinical pathway. ................................................ 58
Figure 9. Example of a simple Markov model, showing transition probabilities. ................... 59
Figure 10. How policy and evaluation interact as part of the decision making process. ....... 75
Figure 11. The ROAMEF Cycle. .......................................................................................... 76
Figure 12. Realist Evaluation Process. ................................................................................ 86
Figure 13. Main methods used in this thesis. ...................................................................... 88
Figure 14. Smoking Prevalence from Integrated Household Survey, 2010-2013. Shown with
95% confidence intervals. ................................................................................................... 92
Figure 15. Routine & Manual Groups – Smoking Prevalence, 2011-2013. Shown with 95%
confidence intervals. ........................................................................................................... 93
Figure 16. Smoking prevalence from Fire Safety Checks. ................................................... 95
Figure 17. Average EQ-5D Index Score, by age group and cannabis use category; never
used, used in last 30 days, or used but not in the last 30 days. There were no individuals
who said they had used in last 30 days in the 16-17 and 65+ age group. ............................ 95
Figure 18. Trend in women smoking at time of delivery (%), Wirral, 2010/11 – 2014/15. ..... 98
Figure 19. Interventions in smoking cessation programme for Wirral. ............................... 100
Figure 20. Smoking prevalence by MSOA (Middle Layer Super Output Area) in Wirral, based
on Health Survey for England synthetic estimates from 2006-08 data. .............................. 103
Figure 21. Probability of surviving next 30 years for male and female smokers and ex-
smokers in Wirral, as predicted by the model. ................................................................... 116
Figure 22. Male smoking behaviour by age for Wirral as predicted by baseline economic
model, showing proportion of total population who are current smokers, ex-smokers and
never smoked, Ages 16 to 90. ........................................................................................... 117
Figure 23. Female smoking behaviour by age for Wirral as predicted by baseline economic
model, showing proportion of total population who are current smokers, ex-smokers and
never smoked, Ages 16 to 90. ........................................................................................... 117
9 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness
Figure 24. Net discounted reduction in disease cases over 20 years, as a result of smoking
cessation activities in Wirral, 2013/14. .............................................................................. 119
Figure 25. Difference in cost per QALY (cost utility) for different quit rates and discount rates.
Wirral smoking economic model........................................................................................ 120
Figure 26. Estimated proportion of adult population who are dependent, higher risk, and
increasing risk drinkers and abstainers in Wirral. Shown as if Wirral were 100 people. ..... 133
Figure 27. Trend in proportion of men and women drinking alcohol, and drinking on more
than 5 days in the last week, Great Britain. ....................................................................... 134
Figure 28. General Health Related Quality of Life (EQ-5D Index) scores from wellbeing
survey 2009 by drinking category. ..................................................................................... 135
Figure 29. Subjective Wellbeing (SWEMWBS) scores from wellbeing survey 2009 by
drinking category. .............................................................................................................. 135
Figure 30. Number of alcohol specific deaths vs. average IMD 2010 deprivation score for
Wirral wards. Based on data from Beynon et al., 2013 matched with data from McClennan et
al., 2011. ........................................................................................................................... 136
Figure 31. Trend in alcohol related admissions in Wirral, sum of alcohol attributable fractions
(AAFs), 2006/07 to 2011/12 financial year. ....................................................................... 138
Figure 32. Spend on different elements of alcohol programme, shown with relationships
between services. ............................................................................................................. 141
Figure 33. Diagram showing costs and benefits associated with alcohol (taken from
Leontaridi, 2003). .............................................................................................................. 144
Figure 34. Structure of alcohol treatment decision tree model. # = the remainder of the
probabilities on each branch. ............................................................................................ 151
Figure 35. Structure of Markov economic model for alcohol residential detoxification. # = 1
minus sum of other probabilities. ....................................................................................... 153
Figure 36. Proportion of specialist alcohol treatment clients by age and gender, 2011/12 FY.
......................................................................................................................................... 154
Figure 37. Proportion of specialist alcohol treatment clients by deprivation category, 2011/12.
......................................................................................................................................... 155
Figure 38. Specialist alcohol treatment model, iterations of incremental cost effectiveness,
with ellipse showing 95% prediction intervals. ................................................................... 160
Figure 39. Cost effectiveness acceptability curve, alcohol specialist treatment showing
probability of alcohol treatment being cost effective vs probability of no treatment being cost
effective at different values of willingness to pay for one QALY. ........................................ 161
Figure 40. Tornado diagram showing one way sensitivity analyses for alcohol specialist
treatment. EV= expected value of net mean benefits. ....................................................... 161
10 Applying Economic Evaluation to Public Health:
Case Studies in Cost Effectiveness