Background

Effective demand creation strategies are needed to increase uptake of medical male circumcision and reduce new HIV infections in eastern and southern Africa. Building on insights from behavioral economics, we assessed whether providing compensation for opportunity costs of time or lottery-based rewards can increase male circumcision uptake in Kenya.

Methods

Uncircumcised men aged 21-39 years were randomized in 1:1:1 ratio to 2 intervention groups or a control group. One intervention group was offered compensation of US $12.50 conditional on circumcision uptake. Compensation was provided in the form of food vouchers. A second intervention group was offered the opportunity to participate in a lottery with high-value prizes on undergoing circumcision. The primary outcome was circumcision uptake within 3 months.

Results

Among 903 participants enrolled, the group that received compensation of US $12.50 had the highest circumcision uptake (8.4%, 26/308), followed by the lottery-based rewards group (3.3%, 10/302), and the control group (1.3%, 4/299). Logistic regression analysis showed that compared with the control group, the fixed compensation group had significantly higher circumcision uptake [adjusted odds ratio 7.1; 95% CI: 2.4 to 20.8]. The lottery-based rewards group did not have significantly higher circumcision uptake than the control group (adjusted odds ratio 2.5; 95% CI: 0.8 to 8.1).

Conclusions

Providing compensation was effective in increasing circumcision uptake among men over a short period. The results are consistent with studies showing that such interventions can modify health behaviors by addressing economic barriers and behavioral biases in decision making. Contrary to findings from studies of other health behaviors, lottery-based rewards did not significantly increase circumcision uptake.

Trial registration

Registry for International Development Impact Evaluations: RIDIE-STUDY-ID-530e60df56107.

Climate variability and change are issues of growing public health importance. Numerous studies have documented risks of extreme heat on human health in different locations around the world. Strategies to prevent heat-related morbidity and reduce disparities are possible but require improved knowledge of health outcomes during hot days at a small-scale level as important within-city variability in local weather conditions, socio-demographic composition, and access to air conditioning (AC) may exist. We analyzed hospitalization data for three unique climate regions of San Diego County alongside temperature data spanning 14 years to quantify the health impact of ambient air temperature at varying exceedance threshold levels. Within San Diego, coastal residents were more sensitive to heat than inland residents. At the coast, we detected a health impact at lower temperatures compared to inland locations for multiple disease categories including heat illness, dehydration, acute renal failure, and respiratory disease. Within the milder coastal region where access to AC is not prevalent, heat-related morbidity was higher in the subset of zip codes where AC saturation is lowest. We detected a 14.6% increase (95% confidence interval [4.5%, 24.6%]) in hospitalizations during hot weather in comparison to colder days in coastal locations where AC is less common, while no significant impact was observed in areas with higher AC saturation. Disparities in AC ownership were associated with income, race/ethnicity, and homeownership. Given that heat waves are expected to increase with climate change, understanding health impacts of heat and the role of acclimation is critical for improving outcomes in the future.