Enhanced patient counselling and SMS reminder messages to improve equitable access to community-based eye care services in Meru, Kenya: An embedded, pragmatic, individual-level, two arm, equity-focused, Bayesian RCT within an adaptive platform trial

BackgroundIn Kenyas Meru county, only 46% of people identified with an eye problem during screening go on to access and receive eye care services at local clinics, with younger adults (those aged 18-44) being the least likely to receive care. In previous work, our team conducted interviews with non-attenders from this left-behind group to explore how access to essential eye services could be equitably improved. They told us that better counselling and SMS reminders would improve access. MethodsWe developed enhanced counselling and SMS reminders with lay input and tested this bundled intervention against standard care using a pragmatic, two-arm randomised controlled trial that was embedded within Merus ongoing screening programme. All consenting referred adults were enrolled. Our primary outcome was the proportion of referred 18-44-year-olds who accessed their local clinic following referral. Following our adaptive platform trial master protocol, our embedded Bayesian-based algorithm used accruing attendance data to calculate the posterior probabilities of effect difference between the arms every seven days. Participants were continually recruited until one of two stopping rules were met: there was a >95% probability that either one arm was more effective, or that the difference between the arms was <1%. FindingsOur testing algorithm stopped the trial after 30 days based on analysis of outcome data from 879 people. We found a 98.6% posterior probability that the intervention arm was superior among 18-44-year-olds. The attendance rate among this group was 32.1% in the control arm vs 39.0% in the intervention arm. Secondary analyses did not show meaningful differences between the arms across the remainder of the population (i.e. adults aged >45 years). DiscussionThis innovative trial found evidence that an intervention bundle suggested by an underserved population group increased access to care. This embedded, adaptive, equity-focused approach has broad applications, aligned with the principle of proportionate universalism.