Could nudges reduce health literacy disparities in CVD prevention? An experiment using alternative messages for CVD risk assessment screening.

Abstract

To explore the effect of SMS nudge messages amongst people with varying health literacy on their intention to get a Heart Health Check. A 3 (Initial SMS: scarcity, regret, or control nudge) x 2 (Reminder SMS: social norm or control nudge) factorial design was used in a hypothetical online experiment. 705 participants eligible for Heart Health Checks were recruited. Outcomes included intention to attend a Heart Health Check and psychological responses. In the control condition, people with lower health literacy had lower behavioural intentions compared to those with higher health literacy (p = .011). Scarcity and regret nudges closed this gap, resulting in similar intention levels for lower and higher health literacy. There was no interactive effect of the reminder nudge and health literacy (p = .724). Scarcity and regret nudge messages closed the health literacy gap in behavioural intentions compared to a control message, while a reminder nudge had limited additional benefit. Health literacy should be considered in behavioural intervention evaluations to ensure health equity is addressed. Results informed a national screening program using a universal precautions approach, where messages with higher engagement for lower health literacy groups were used in clinical practice.