The provision of regular low-value economic incentives can improve adherence to antiretroviral therapy (ART), according to research conducted in Uganda. People were eligible for prizes worth approximately $1.50 if they attended their clinic appointments or took at least 90% of the ART doses as evaluated using electronic monitoring.
“In this study we present evidence that it is feasible and effective to use small behavioural economics incentives to increase ART adherence,” comment the authors led by Sebastian Linnemayr, senior economist at the RAND Corporation and a professor at the Pardee RAND Graduate School. “Our study suggests that designing incentives based on behavioural economic insights can increase their effectiveness, and get beyond the often at best mixed results of recent interventions aimed at behavioural change in the HIV field based on traditional, fixed incentives of relatively large monetary value.”
Adherence is key to the success of ART. Missed doses or prolonged unscheduled treatment interruptions can lead to viral breakthrough and the emergence of drug-resistant virus. Many people find it hard to achieve the high levels of adherence which ART demands. Research examining whether the provision of fixed economic incentives of relatively high value (usually in cash) has a positive impact on health-associated behaviours among people with HIV has had mixed results.
An alternative incentive approach uses behavioural economics and involves the provision of regular small incentives for achieving health-related targets.
Investigators in Kampala, Uganda, designed a randomised study involving 144 ART-experienced adults to see if small incentives using the behavioural economics theory increased adherence to ART.
The study population was drawn from adults receiving care at Mildmay, Uganda. All were ART-experienced (minimum two years of therapy) and had documented adherence problems.
They were randomised to receive standard of care, or into one of two intervention groups. People in these intervention groups were eligible for prizes such as coffee mugs, umbrellas or water bottles for timely attendance at clinic appointments (group one) or for taking at least 90% of their ART doses, measured electronically using MEMS (group two).
The study is intended to last two years; the investigators reported on the first nine months.
Over half the participants had completed primary education, two-thirds were women and the average age was 39 years. Median monthly disposable income was the equivalent of $58, of which 5% was spent on travel to clinic appointments. Approximately 12% were physically limited because of their health and 65% reported feelings of depression or hopelessness.
Individuals in the control group had an overall adherence rate of 81%, compared to 88% among those in intervention group one and 87% for people in group two. These differences were of borderline significance.
However, further analysis showed that the impact of the interventions was most pronounced around the target 90% adherence threshold. Just 40% of people in the control arm were able to manage this level of adherence, compared to 63% of people in the two intervention groups. The effect was most pronounced among those whose adherence was monitored using the MEMS system.
“A larger, fully powered study is needed to confirm these early promising results and would allow the results to additionally detect demographic subgroup differences to shed light on the characteristics of patients most likely to benefit from the intervention,” suggest the authors. “In the current study, those with relatively high (but not optimal) adherence seem to be benefiting disproportionately from the intervention, which is in line with our hypothesis that for our study sample of treatment-mature clients motivational rather than structural barriers are addressed by the small incentives offered.”
Objective: Fixed incentives have been largely unsuccessful in improving adherence to antiretroviral (ARV) medication. Therefore we evaluate whether small incentives based on behavioral economic theory can increase adherence to ARV medication among treatment-mature adults in Kampala, Uganda.
Design: A randomized control trial design tests whether providing small incentives based on either attending timely clinic visits (intervention group 1) or achieving high medication adherence (intervention group 2) can increase ARV adherence. ARV adherence is measured by medical event monitoring system (MEMS) caps.
Methods: 155 HIV infected men and women age 19-78 were randomized into one of two intervention groups and received small prizes of US $1.50 awarded through a drawing conditional on either attending scheduled clinic appointments or achieving at least 90% ARV adherence. The control group received the usual standard of care.
Results: Preliminary results based on pooling the intervention groups showed individuals receiving incentives were 23.7 percent points more likely to achieve 90% ARV adherence compared to the control group (95% CI, 6.7 – 40.7%). Further, 63.3% (95% CI, 52.9 – 72.8%) of participants in the pooled intervention groups maintained at least 90% mean adherence during the first nine months of the intervention, compared to 39.6% (95% CI, 25.8 – 54.7%) in the control group.
Conclusion: Small prize incentives resulted in a statistically significant increase in ARV adherence. While more traditional fixed incentives have not produced the desired results, these findings suggest that small incentives based on behavioral economic theory may be more effective in motivating long-term adherence among treatment-mature adults.
Linnemayr, Sebastian; Stecher, Chad; Mukasa, Barbara