Publication: 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
Date
2023-09-26
ISSN
Published
2023-09-26
Author(s)
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.
Link to Data Set
Citation
“Balampama, Marianna; de Walque, Damien; Dow, William H.; Hémono, Rebecca. 2023. 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 Papers; 10571. © World Bank, Washington, DC. http://hdl.handle.net/10986/40395 License: CC BY 3.0 IGO.”
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