Effect of Behaviourally Informed Text Messages to Promote Retention in HIV Care: A Randomized Trial in Ekurhuleni District, South Africa

IntroductionSustained engagement in care among people living with HIV is vital for realising the individual and public health benefits of antiretroviral therapy (ART). We examined whether mobile phone-based text messages that leveraged behavioural science principles promoted timely clinic attendance among ART recipients. MethodsWe conducted a randomized controlled trial in three primary health clinics in Gauteng Province, South Africa between July 2021 and December 2021. ART recipients with an upcoming clinic appointment were randomised to standard of care appointment reminders or three enhanced reminders that leveraged behavioural science principles of loss aversion, social norms, and altruism. The primary outcome was a timely clinic visit, on or before the scheduled appointment day. Poisson regression with clinic fixed effects and controls for age, sex, and ART duration was used to examine the effect of the enhanced reminders on the primary outcome. ResultsAmong 1539 participants, 690 (44.8%) were male and median time on ART was 11 months (IQR, 3.7-51.9). The primary outcome of timely clinic visit was 50.3% in the standard of care arm, and similar in the loss aversion arm (53.5%; adjusted risk ratio, ARR 1.1; 95% CI: 0.9-1.2), social norms arm (48.0%; ARR 1.1; 95% CI: 0.8-1.1), and altruism arm (50.9% ARR 1.0; 95% CI: 0.9-1.5). In subgroup analyses, messages framed with loss aversion increased the timely clinic visits among participants with ART duration <90 days (ARR=1.37; 95% CI: 1.08-1.74). ConclusionsThe use of behavioural science principles to frame reminder messages did not increase timely clinic visits among HIV care recipients. Among those who recently initiated ART, however, loss aversion framing increased timely clinic visits. Future research should explore alternative behavioural science principles to revise health communication with HIV care recipients. Clinical Trials NumberNCT05010291