Behaviourally-Informed Two-Way Text Messaging to Improve Return to HIV Care in South Africa: Evidence from a Randomised Controlled Trial.

One-way text messaging to re-engage people in HIV care has shown promise, but little is known about two-way messaging. We evaluated a behaviourally-informed two-way text messaging intervention to increase re-engagement in care following missed visits. We conducted an individual-level randomised controlled trial between February and March 2023 in Capricorn District, South Africa. Adults aged ≥ 18 years who had missed an ART visit by > 28 days were randomised to (1) a standard one-way text message, or (2) behaviourally-informed two-way text messages. The primary outcome was return to care within 45 days, analysed as (1) intention to treat, and (2) restricted to successful message delivery. 3,695 participants were randomised: 1,845 to the one-way message group and 1,850 to the two-way message group. 27.9% (515/1845) of participants sent a one-way message and 27.2% (503/1850) sent a two-way message returned for an ART visit within 45 days (proportion difference: -0.7%, p-value: 0.622). In an analysis restricted to participants whose text message was delivered, 28.3% (310/1094) in the one-way message group compared to 28.3% (304/1076) in the two-way message group returned to care (proportion difference: -0.09%, p-value: 0.966). 19.5% (210/1076) responded to the two-way message. The two most reported reasons for missed appointments were being out of town (41.0%) and still having medication (31.0%.). Behaviourally-informed two-way text messages did not improve return to care over one-way messages. However, they elicited reasons for disengagement. Additional research is needed on the mode, content and timing of two-way messages intended to increase return to care.Clinical Trial Number: PACTR202202748760768 & DOH-27-042022-6703. 28 February 2022.