Abstract
IMPORTANCE: Novel strategies are needed to increase the uptake of voluntary medical male circumcision (VMMC) in sub-Saharan Africa and enhance the effectiveness of male circumcision as an HIV prevention strategy. OBJECTIVE: To determine whether small economic incentives could increase circumcision prevalence by addressing reported economic barriers to VMMC and behavioral factors such as present-biased decision making. DESIGN, SETTING, AND PARTICIPANTS: Randomized clinical trial conducted between June 22, 2013, and February 4, 2014, among 1504 uncircumcised men aged 25 to 49 years in Nyanza region, Kenya. VMMC services were provided free of charge and participants were randomized to 1 of 3 intervention groups or a control group. INTERVENTIONS: Participants in the 3 intervention groups received varying amounts of compensation conditional on undergoing circumcision at 1 of 9 study clinics within 2 months of enrollment. Compensation took the form of food vouchers worth 200 Kenya shillings (≈ US $2.50), 700 Kenya shillings (≈ US $8.75), or 1200 Kenya shillings (≈ US $15.00), which reflected a portion of transportation costs and lost wages associated with getting circumcised. The control group received no compensation. MAIN OUTCOMES AND MEASURES: VMMC uptake within 2 months. RESULTS: Analysis of data for 1502 participants with complete data showed that VMMC uptake within 2 months was higher in the US $8.75 group (6.6%; 95% CI, 4.3%-9.5% [25 of 381]) and the US $15.00 group (9.0%; 95% CI, 6.3%-12.4% [34 of 377]) than in the US $2.50 group (1.9%; 95% CI, 0.8%-3.8% [7 of 374]) and the control group (1.6%; 95% CI, 0.6%-3.5% [6 of 370]). In logistic regression analysis, the US $8.75 group had significantly higher VMMC uptake than the control group (adjusted odds ratio [AOR] 4.3; 95% CI, 1.7-10.7), as did the US $15.00 group (AOR 6.2; 95% CI, 2.6-15.0). Effect sizes for the US $8.75 and US $15.00 groups did not differ significantly (P = .20). CONCLUSIONS AND RELEVANCE: Among uncircumcised men in Kenya, compensation in the form of food vouchers worth approximately US $8.75 or US $15.00, compared with lesser or no compensation, resulted in a modest increase in the prevalence of circumcision after 2 months. The effects of more intense promotion or longer implementation require further investigation. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01857700.