1A.002 Factors associated with participant attrition in an app-based unintentional child injury intervention

Background High attrition rates threaten evaluation of the effectiveness of mobile health interventions. We explored the factors associated with attrition of study participants in an app-based clinical trial. Methods This six-month cluster randomized control trial (RCT) implemented two app-based interventions: an unintentional child injury prevention app in the intervention group (Bao Hu San) and a nutrition app in the control group. The study included 2,920 caregivers of 3–6 year-old preschoolers in Changsha, China. Follow-up surveys were conducted 3 and 6 months after baseline, and data on app engagement was collected electronically during the RCT. Associations within intervention and control groups were tested and quantified separately using adjusted odds ratio (aOR) based on logistic regression models. Results The six-month attrition rate was 32.2%. Attrition rates differed significantly between control and intervention groups (35.7% vs. 28.9%, p Conclusions Demographic characteristics and app engagement were associated with attrition. Learning Outcomes Researchers and practitioners should consider demographic factors and engagement when designing app-based interventions.