RT Journal Article SR Electronic T1 Randomised controlled trial of incentives to improve online survey completion among internet-using men who have sex with men JF Journal of Epidemiology and Community Health JO J Epidemiol Community Health FD BMJ Publishing Group Ltd SP 156 OP 161 DO 10.1136/jech-2018-211166 VO 73 IS 2 A1 Hall, Eric A1 Sanchez, Travis A1 Stephenson, Rob A1 Stein, Aryeh D A1 Sineath, Robert Craig A1 Zlotorzynska, Maria A1 Sullivan, Patrick YR 2019 UL http://jech.bmj.com/content/73/2/156.abstract AB Background HIV prevention research often involves the use of online surveys as data collection instruments. Incomplete responses to these surveys can introduce bias. We aimed to develop and assess innovative methods to incentivise respondents to complete surveys.Methods Adult men who have sex with men (MSM) living in the USA were recruited through banner advertisements on Facebook from 27 April 2015 to 6 May 2015 to participate in an online survey about HIV prevention and risk behaviours. Participants were randomised to one of four conditions: a monetary incentive; a series of altruistic messages highlighting the importance of participating in research; access to a dashboard comparing their responses with statistics from other participants after completion; and no incentive. Kaplan-Meier survival methods and univariate Cox proportional hazard models were used to evaluate survey dropout by incentive group and demographic variables of interest.Results There were a total of 1178 participants randomised to the four treatment groups. The rate of survey dropout among participants in the altruistic (HR=0.68, 95% CI 0.49 to 0.93), monetary (HR=0.44, 95% CI 0.32 to 0.61) and dashboard (HR=0.78, 95% CI 0.58 to 1.06) groups was lower than the non-incentivised control group. Regardless of condition, survey dropout was also lower among MSM aged 28–34 (HR=0.67, 95% CI 0.50 to 0.90) compared with those aged 18–22 years old, and MSM who were white (HR=0.78, 95% CI 0.60 to 1.02) compared with non-white participants.Conclusion Monetary incentives and altruistic messaging can improve survey completion in online behavioural HIV prevention research among MSM.Trial registration number NCT02139566.