Effectiveness of WhatsApp based debunking reminders on follow-up visit attendance for individuals with hypertension: a randomized controlled trial in India

BACKGROUND: Individuals with high blood pressure in India often miss essential follow-up visits. Missed visits contribute to gaps across the hypertension care continuum and preventable cardiovascular disease. Widespread misconceptions around hypertension care and treatment may contribute to low follow-up attendance rates, but to date, there is limited evidence of the effect of interventions to debunk such misconceptions on health-seeking behavior. We conducted a randomized controlled trial to measure whether combining information debunking commonly-held misconceptions with a standard reminder reduces missed follow-up visits among individuals with high blood pressure and investigated whether any observed effect was moderated through belief change. METHODS: We recruited 388 patients with uncontrolled blood pressure from the outpatient wards of two public sub-district hospitals in Punjab, India. Participants randomly assigned to the intervention arm received two WhatsApp messages, sent 3 and 1 days before their physician-requested follow-up visit. The WhatsApp message began with a standard reminder, reminding participants of their upcoming follow-up visit and its purpose. Following the standard reminder, we included brief debunking statements aimed at acknowledging and correcting common misconceptions and misbeliefs about hypertension care seeking and treatment. Participants in the control group received usual care and did not receive any messages. RESULTS: We did not find evidence that the enhanced WhatsApp reminders improved follow-up visit attendance (Main effect: 2.2 percentage points, p-value = 0.603), which remained low across both treatment (21.8%, 95% CI: 15.7%, 27.9%) and control groups (19.6%, 95% CI: 14.2%, 25.0%). Participants had widespread misconceptions about hypertension care but our debunking messages did not successfully correct these beliefs (p-value = 0.187). CONCLUSIONS: This study re-affirms the challenge of continuity of care for chronic diseases in India and suggests that simple phone-based health communication methods may not suffice for changing prevalent misconceptions and improving health-seeking behavior. TRIAL REGISTRATION: The trial began on July 18th. We registered the trial on July 18th (before recruitment began), including the main outcomes, on the German Clinical Trial Register [Identifier: DRKS00029712] and published a pre-analysis plan in the Open Science Framework [osf.io/67g35].