ABC Project Update

WP2: Discrete choice experiment design

Dyfrig Hughes, Emily Fargher, Val MorrisonABC Project Working MeetingSeptember 2009

Behaviourintention

Demographicse.g. age, gender

Personality

Past experience

Outcome expectancies Xoutcome value

Normative beliefsX motivation to comply

Perceived internal and external control factors

Attitude towardsbehaviour

Subjective norm

Perceived behaviouralcontrol

BEHAVIOUR

Time Pref. Questions(Economic theory)

LOT(Optimism)

TPB QuestionnaireAdapted MDQ

(Theory of planned behaviour)

MDQ Add On(Behaviour intention)

Bilateral Bargaining(Economic theory)

BMQ(Self-regulation theory)

Brief-IPQ(Self-regulation theory)

Health Beliefs Model

DCE(Stated preference)

MARS(Adherence measure)

Morisky(Adherence measure)

TPB: ABC Questionnaire Map

Prospect theory

Time preference

Humancapital

Questionnaire suggestions

Questionnaire No. items

Measure / Theory

MARS 5 Adherence

Morisky 8/4 Adherence

Breif_IPQ 9 Self-regulation theory

BMQ 11 Self-regulation theory

LOT_R 10 Optimism

TPB (Adapt_MDQ)

15 Theory of planned behaviour

Time Preference

4/2 Time preference

DCE 16 Stated preference

Discrete choice experiments Developed in the 1990s to elicit views on health care Based on the idea that goods and services are described

by characteristics (attributes) The levels of these characteristics determines the extent

to which the individual values these goods and service DCE is used to

Show how people are willing to trade between characteristics Produce overall benefit scores for alternative ways of providing

health care Estimate the relative importance of different characteristics of a

service Estimate whether an attribute is important

Example choice question

Rank

Binary choice

Varying levelsAttributes

Hypothetical scenario

Recent example

DCE methodology

1. Identification of attributes Policy, RCTs, literature Source: policy, RCTs, literature

2. Identification of associated levels ACTIONABLE, PLAUSIBLE and capable of being TRADED OFF

Cardinal (dose frequency OD, BD) Ordinal (severe vs. moderate ADR) Categorical (GP versus pharmacist)

3. Design choice scenarios4. Questionnaire 5. Input, analysis and interpretation

U = β1Sym + β2Freq + β3S_ADR + β4M_ADR ... + e

Checklist!Lancsar E. & Louviere J. (2008) Conducting discrete choice experiments to inform healthcare decision making. Pharmacoeconomics 26(8): 661-677.

Stage 1&2

Stage 3: Choice scenarios

Greater the number of attributes and levels, the greater the number of possible profiles

Possible profiles = LevelsAttributes

2 attributes at 2 levels = 22 = 4 4 attributes at 4 levels = 44 = 256 3 attributes at 3 levels and 1 attributes at 2 levels

= 33 x 21 = 54 Design catalogue e.g. http://www.research.att.com/~njas/oadir/ 24 runs

Substantial questionnaire of Multiple pages Coast J., Flynn T.N., Sailsbury C., Louviere J., & Peters T.J. (2006)

Maximising responses to discrete choice experiments - a randomised trial. Appl Health Econ Health Policy 5(4): 249-260.

What next?

Confirm survey content Confirmation of questionnaires to be inc. in

survey Confirmation of DCE design (length)

Translation Validation of instruments Co-ordination of ethics Pilot – all countries?

ABC Project Update

WP3: Econ & psychological determinants review

Dyfrig Hughes, Emily Fargher, Val MorrisonABC Project Working MeetingSeptember 2009

ABC WP3

Systematic Review of behavioural models of adherence to medicines: Economic & psychological perspectives

T3.1 “Systematic review of the literature: Studies that have assessed the psychological and economic basis for non-compliance, together with structured models of compliance behaviour will be identified using computerised search in relevant databases, retrieved and analysed.”

Review Question: Which models in the economics and psychology literature may explain adherence to medicine?

Search strategy

A series of independent search strategies, across databases, will be used to identify papers in the economics and psychology literature.

For consistency the search strategy used to identify adherence papers in WP1 will be used throughout this work package.

Databases to be searched: MEDLINE, EMBASE, The Cochrane Library, CINAHL, PsycINFO, PsycLit, EconLit

Inclusion Criteria: Papers containing EMPRICIAL data reporting adherence OR reporting a behavioural model or theory or adherence

Exclusion Criteria: Non-pharmaceutical studies

Search strategy stages

Search OneEconomic models

based on cost

1. Adherence terms2. Cost terms3. 1 AND 24. Limit 3 to review

Search TwoEconomic models

exc. cost

1. Adherence terms2. Econ theory terms3. 1 AND 2

Search ThreeAll other

economic models

1. Adherence terms2. Generic catch all3. Econ Eval. terms 4 2 NOT 35. 1 AND 4

Search FourPsychological models

1. Adherence terms2. Psychological theory terms3. 1 AND 2

Search FiveAll other

psychological models

1. Adherence terms2. Generic catch all 3. 1 AND 2

Economic models Psychological models

screen all papers using the same criteria

Strategy examples

What next?

Held teleconference and decided …

Run searches & re-convene in October to agree next stage: Independent screen of titles and abstracts by 2 reviewers Data Extraction:

Study characteristics Measure of adherence (+ critique of measure of adherence) Key Findings Behavioural model e.g. Consumer choice theory, Theory of planned

behaviour etc. (+ Critique of experiment used to test model)

Final stage: using results of review & expertise within the group develop the model.

Thank you

Dyfrig Hughes, Emily Fargher, Val MorrisonABC Project Working MeetingSeptember 2009