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Fields Changed

Registration

Field Before After
Study Withdrawn No
Intervention Completion Date May 31, 2021
Data Collection Complete Yes
Final Sample Size: Number of Clusters (Unit of Randomization) 2,206 women
Was attrition correlated with treatment status? Yes
Final Sample Size: Total Number of Observations 1,117 women
Final Sample Size (or Number of Clusters) by Treatment Arms 508 women control, 609 women treatment
Data Collection Completion Date January 31, 2022
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Papers

Field Before After
Paper Abstract Female sex workers are a key population who experience a disproportionately high burden of HIV and sexually transmitted infections. A growing body of evidence suggests that financial incentives can reduce risky sexual behavior and the incidence of HIV and sexually transmitted infections; however, few studies have examined a lottery-based incentive mechanism or been conducted with female sex workers. This paper examines the effect of a lottery intervention on the combined incidence of HIV and herpes simplex virus 2 among female sex workers in Tanzania. The RESPECT II trial was an unmasked, two-arm, parallel group randomized controlled trial conducted in Dar es Salaam, Tanzania among 2,206 enrollees from 2018 to 2021. Participants were randomized in a one-to-one ratio to the basic test control group or to the lottery intervention group. The basic test group received testing and counseling for HIV and biweekly text messages with information on safe sex practices. The lottery group received the basic test group intervention plus entry into a weekly lottery with a 100,000 Tanzanian shilling (US$50) reward offered to 10 randomly selected participants, conditional on negative test results for syphilis and trichomonas. The primary outcome was combined HIV and herpes simplex virus 2 incidence after 36 months. The results showed no statistically significant effect on this primary outcome. Thus the study finds no evidence that the lottery-based incentives reduced the incidence of HIV and sexually transmitted infections among the female sex worker population. However, the results may have been affected by disruption from the COVID-19 pandemic, and unexpectedly high study attrition levels made it impossible to statistically rule out possible moderate-sized effects.
Paper Citation Balampama,Marianna; De Walque,Damien B. C. M.; Dow,William H.; Hémono,Rebecca. "Effects of a Lottery Incentive on Sexually Transmitted Infections and HIV Incidence among Female Sex Workers in Tanzania: Results from the RESPECT II Randomized Trial." Policy Research working paper no. WPS 10571. Washington, D.C.: World Bank Group.
Paper URL http://documents.worldbank.org/curated/en/099428309252326332/IDU08c3a9fc50f8b6041ec08d0f0637e616ccd54
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