Effect of a Prize-Linked Savings Intervention on Savings and Healthy Behaviors Among Men in Kenya: A Randomized Clinical Trial.

Importance: Interventions to reduce men's alcohol use and risky sexual behaviors are essential for reducing new HIV infections in high-prevalence settings in sub-Saharan Africa. Prize-linked savings accounts can motivate savings and may decrease expenditures on risky behaviors, but few studies have examined the HIV prevention potential of such savings interventions among men. Objective: To evaluate the effect of prize-linked savings accounts on savings behavior and expenditures on alcohol, gambling, and transactional sex among men in Kenya. Design, Setting, and Participants: Randomized clinical trial among communities in Siaya County, Kenya. Participants were men 21 years or older who owned a mobile phone, were engaged in fishing or transportation sector work, and were willing to open an account with a local bank; they were screened for eligibility between September 3 and October 5, 2018. Interventions: Eligible participants were offered savings accounts endowed with 1000 Kenya shillings (US $10) and randomized (1:1) to receive weekly lottery-based rewards contingent on growth in savings balance or to a control group that received standard interest. Main Outcomes and Measures: The primary outcome was an indicator of whether a participant saved any money in the bank account (intent-to-treat analysis) during the study period. Secondary outcomes included total amount saved in the bank account, total amount saved in all sources, and expenditures on alcohol, gambling, and transactional sex. Results: A total of 425 men were screened, 329 (77.4%) met eligibility criteria, 300 (70.6%) were enrolled (with 152 randomized to the intervention group and 148 to the control group), and 270 of 300 (90.0%) opened bank accounts. Participants' mean age was 33.7 years (interquartile range, 13.5 years), 84.3% (253 of 300) were married, and the mean weekly earnings were US $30 (interquartile range, US $23). During a mean (SD) follow-up of 9 (2) weeks, 37.3% (50 of 134) in the intervention group saved money in a bank account vs 27.2% (37 of 136) in the control group, although the difference was not statistically significant (odds ratio, 1.62; 95% CI, 0.96-2.74). The intervention group had higher growth in bank savings balances (US $10.26; 95% CI, US $5.00-US $58.20 vs US $4.87; 95% CI, US $0.67-US $9.00) and higher total savings from all sources (US $201; 95% CI, US $133-US $269 vs US $145; 95% CI, US $88-US $202), but neither difference was statistically significant. The intervention did not have a significant effect on alcohol, gambling, and transactional sex expenditures. Conclusions and Relevance: Prize-linked savings accounts modestly increased savings among high-risk men in Kenya over a 9-week period, but the difference compared with standard-interest savings accounts was not significant. Testing of more powerful savings products is needed to assess whether such savings-led interventions can reduce men's expenditures on alcohol, gambling, and transactional sex. Trial Registration: Social Science Registry identifier: AEARCTR-0003224, and ClinicalTrials.gov identifier: NCT04013295.