An Area of Opportunity? Using
Clinical Trials to Evaluate Positive
Financial Incentives for Patients to
Improve HIV and TB Diagnosis,
Care, and Treatment
Bruce A. Larson, PhD
Center for Global Health and Development,
Department of International Health—School of Public Health,
Boston University
June 20, 2010
Health Economics and Epidemiology Research Office
HE RO
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Wits Health Consortium
University of the Witwatersrand
Introduction: Two roles for economics in
clinical trials with randomized designs
• Cost-effectiveness analysis for the evaluation
of biomedical interventions
• Draw on economics as a social/behavioral
science for the design and evaluation of
behavioral interventions
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Basic insights from economics for the
design of behavioral interventions
• Standard economics = neoclassical economics
– people are rational and know what they want, they
are good at processing information and making
decisions but constrained by income and prices
– so, lower a price and/or provide better information to
stimulate demand (adopt behavior change,
compliance)
• Types of interventions amenable to RCT design based
on this logic?
– provide transport vouchers to patients to reduce the
cost of clinic visits
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Additional ideas from economics for the
design of behavioral interventions?
• behavioral economics incorporates information from
psychology and other social sciences, such as
– Individuals have self-control problems
– Individuals have problems with processing information
– Individual preferences may not be stable over time and may not
be based solely on self-interest
• Interventions amenable to RCT design?
– targeted, modest, positive financial incentives may overcome
self-control and information processing problems
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Opportunities for randomized controlled
trials of behavioral interventions in HIV
and TB
• Intervention  use positive financial incentives
(direct or indirect payments in cash or close
alternatives) to encourage patients to complete
various steps in diagnosis, care, and treatment.
• Positive incentive programs have been widely used
in health care as well as other areas of social policy
including education and labor.
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For example:
• When HIV-infected patients provide blood samples for
CD4 testing, they are asked to return in a few days to
obtain results (and continue with appropriate care and
treatment depending on result)
• In South Africa, perhaps 50% of patients actually return
within a several-month period to obtain their results
• How do we encourage more patients to return for their
CD4 count results in a timely manner?
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Example (continued):
• Intervention – provide positive financial
incentive to patient if he/she returns for results.
• Key – intervention must be known to patient in
advance (e.g. when blood sample obtained),
with payment conditional on future appropriate
behavior.
• Appropriate to evaluate the effectiveness and
cost-effectiveness of such interventions with a
randomized clinical trial design.
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Are positive financial incentives for
patient behavior ethical?
• Does the positive incentive support behavior that
is socially preferred?
• Does the positive incentive support what an
individual might want to do in the absence of
barriers to adopting the behavior?
– Barriers  financial, social pressure, information
processing, self-control (short-term/long-term
preferences)
– Experience that modest incentives can work (not
large enough to be coercive).
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When do positive financial incentives work?
• Positive financial incentives can change behavior when
– The definition of compliance is clear (what people need to
do to receive payment)
– Compliance involves a specific time limit
– The required behavior is relatively simple (e.g., keeping
appointments)
– People trust that the payment will be made
• Conversely, incentive programs are less effective when
– Behavioral change is complex
– Requires long term adherence
– Examples: smoking cessation, lifestyle change, weight
loss, etc.
• But, newer behavioral economics research suggests
sometimes effective for more complex situations (Lussier,
Heil et al. 2006).
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Opportunities for incentive-based
interventions for HIV and TB care
•
HIV
– Early diagnosis of high-risk, asymptomatic populations
– Completion of staging and enrollment in appropriate care
– Adherence to pre-ART or ART visit schedule
•
TB
– Completion of treatment
– Diagnosis of asymptomatic or mildly symptomatic high-risk
populations
– Contact tracing (incentivize patient to bring contacts for testing)
•
Each of these interventions could be evaluated with a randomized
evaluation design.
– Effectiveness = change in compliance
– Cost = additional cost of implementing incentive program
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Detailed structure of the intervention
clearly matters
• amount of the incentive payment
• when and where the intervention is explained to
patients
• criteria for compliance clear (trust payment made,
excludes cheaters)
• the method of payment (cash, voucher, other)
• when, where, and from whom the patients receive the
payment (nurse, counselor, pharmacy, elsewhere)
• details as important as level of payment
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Final Remarks
• Potential for incentive-based behavioral
interventions to improve outcomes when
patient compliance required
– amenable to evaluation within RCT design
• Potential to target such interventions to
health workers as well (and evaluate in
RCT design)
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Final Remarks
• Levels of randomization?
– patient, clinic, community, or other units feasible (not feasible to
randomize incentive within same facility)
• Policy relevance
– intervention feasible to implement outside study setting
– avoids unwanted behavior (cheating, perverse incentives)
• Substantial experience in economics with evaluation of
randomized interventions
– at least a few hundred randomized controlled
evaluations have been conducted on a range of
interventions
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References
Jochelson, K., Paying the Patient: Improving Health
Using Financial Incentives. 2007, King's Fund.
Sindelar, J.L., Paying for performance: the power of
incentives over habits. Health Economics, 2008. 17(4):
p. 449-451.
LUSSIER, J., HEIL, S., MONGEON, J., BADGER, G. &
HIGGINS, S. (2006) A meta-analysis of voucher-based
reinforcement therapy for substance use disorders.
Addiction, 101, 192-203.
Acknowledgements
• Boston University and the Health Economics and
Epidemiology Research Office, University of the
Witwatersrand
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Sydney Rosen
Lawrence Long
Gesine Meyer-Rath
Matthew Fox
Bibi Ndibongo
Ian Sanne
• Right to Care
• U.S. Agency for International Development / South
Africa
• PEPFAR