A 5-Year Review of the Impact of Lottery Incentives on HIV-Related Services.

PURPOSE OF REVIEW: Lottery incentives are an innovative approach to encouraging HIV prevention, treatment initiation, and adherence behaviours. This paper reviews the latest research on lottery incentives' impact on HIV-related services, and their effectiveness for motivating behaviours to improve HIV service engagement and HIV health outcomes. RECENT FINDINGS: Our review of ten articles, related to lottery incentives, published between 2018 and 2023 (inclusive) shows that lottery incentives have promise for promoting HIV-related target behaviours. The review highlights that lottery incentives may be better for affecting simpler behaviours, rather than more complex ones, such as voluntary medical male circumcision. This review recommends tailoring lottery incentives, ensuring contextual-relevance, to improve the impact on HIV-related services. Lottery incentives offer tools for improving uptake of HIV-related services. The success of lottery incentives appears to be mediated by context, the value and nature of the incentives, and the complexity of the target behaviour.

Are vaccine lotteries worth the money?

This research evaluates the effects of the twelve statewide vaccine lottery schemes that were announced as of June 7, 2021 on state vaccination rates. We construct a dataset that matches information on the timing and location of these lotteries with daily, county-level data from the U.S. Centers for Disease Control (CDC) on the cumulative number of people who have received at least one dose of an emergency-authorized Covid-19 vaccine. We find that 10 of the 12 statewide lotteries studied (i.e., all but Arkansas and California) generated a positive, statistically significant, and economically meaningful impact on vaccine uptake after thirty days. On average, the cost per marginal vaccination across these programs was approximately $55.

A Randomized, Controlled Trial of Lottery-Based Financial Incentives to Increase Physical Activity Among Overweight and Obese Adults.

PURPOSE: To evaluate the effect of lottery-based financial incentives in increasing physical activity. DESIGN: Randomized, controlled trial. SETTING: University of Pennsylvania Employees. PARTICIPANTS: A total of 209 adults with body mass index ≥27. INTERVENTIONS: All participants used smartphones to track activity, were given a goal of 7000 steps per day, and received daily feedback on performance for 26 weeks. Participants randomly assigned to 1 of the 3 intervention arms received a financial incentive for 13 weeks and then were followed for 13 weeks without incentives. Daily lottery incentives were designed as a "higher frequency, smaller reward" (1 in 4 chance of winning $5), "jackpot" (1 in 400 chance of winning $500), or "combined lottery" (18% chance of $5 and 1% chance of $50). MEASURES: Mean proportion of participant days step goals were achieved. ANALYSIS: Multivariate regression. RESULTS: During the intervention, the unadjusted mean proportion of participant days that goal was achieved was 0.26 in the control arm, 0.32 in the higher frequency, smaller reward lottery arm, 0.29 in the jackpot arm, and 0.38 in the combined lottery arm. In adjusted models, only the combined lottery arm was significantly greater than control ( P = .01). The jackpot arm had a significant decline of 0.13 ( P < .001) compared to control. There were no significant differences during follow-up. CONCLUSIONS: Combined lottery incentives were most effective in increasing physical activity.