Objective: To assess the comparative effectiveness of alternative incentive-based interventions to promote HIV testing among men.
Design: Randomized clinical trial.
Methods: We enumerated four Ugandan parishes and enrolled men at least 18 years. Participants were randomized to six groups that received incentives of varying type and amount for HIV testing at a 13-day community health campaign. Incentive types were: gain-framed (control): participants were told they would receive a prize for testing; loss-framed: participants were told they had won a prize, shown several prizes, asked to select one, then told they would lose the prize if they did not test; lotteries: those who tested had a chance to win larger prizes. Each incentive type had a low and high amount (∼US$1 and US$5/participant). The primary outcome was HIV-testing uptake at the community health campaign.
Results: Of 2532 participants, 1924 (76%) tested for HIV; 7.6% of those tested were HIV-positive. There was no significant difference in testing uptake in the two lottery groups (78%; P = 0.076) or two loss-framed groups (77%; P = 0.235) vs. two gain-framed groups (74%). Across incentive types, testing did not differ significantly in high-cost (76%) vs. low-cost (75%; P = 0.416) groups. Within low-cost groups, testing uptake was significantly higher in the lottery (80%) vs. gain-framed (72%; P = 0.009) group.
Conclusion: Overall, neither offering incentives via lotteries nor framing incentives as losses resulted in significant increases in HIV testing compared with standard gain-framed incentives. However, when offering low-cost incentives to promote HIV testing, providing lottery-based rewards may be a better strategy than gain-framed incentives.