Evaluation of an EAST Nudge-Based Oral Health Promotion Leaflet for Workers: A Six-Month Randomized Controlled Trial

Some workers procrastinate oral care because of cognitive biases and nudges have been proposed as useful interventions to address this problem. This study, a randomized controlled trial, evaluated workers' oral care behaviours 6 months after an Easy-Attractive-Social-Timely (EAST) nudge-based leaflet was distributed.

Participants were recruited and surveyed online, whereas the intervention leaflet was delivered by postal mail. Participants in the control group received a text-based leaflet providing detailed information on oral care. Participants in the nudge group received a nudge-based leaflet. The persuasive text was shortened by more than 70% compared with the control leaflet (easy nudge), incorporated a narrative comic to elicit peer-related behaviours (attractive and social nudges), and featured a cover designed to prompt immediate reading (timely nudge). The outcomes were changes in oral self-care, self-monitoring, professional preventive care, stages of behavioural change, and health literacy, measured using established assessment scales.

In the intention-to-treat analysis, 119 participants in the nudge group and 120 in the control group were analysed. No significant between-group differences were observed for any outcome, including improvement in oral self-care frequency (18.5% vs. 13.3%, respectively; p = 0.147).

This is one of the few randomized controlled trials reporting non-significant findings on oral health nudges, suggesting that an EAST-based leaflet may have limitations in sustaining long-term behaviour change in this setting. Options for future interventions may include using the EAST-based leaflet in different contexts, such as a supplementary resource during face-to-face health education sessions.