Fig. 5: This figure illustrates the relationship between the total number of persuasive design principles implemented in digital mental health interventions (PD_TOTAL) and intervention efficacy, measured by Hedges’ g effect sizes.
From: A meta-analysis of persuasive design, engagement, and efficacy in 92 RCTs of mental health apps
Each point represents an individual study, with point size reflecting study weight in the meta-regression. The shaded region represents the 95% confidence interval around the regression line. The analysis found no significant relationship between the number of persuasive design principles and intervention efficacy, b = 0.01, SE = 0.02, 95% CI [−0.04, 0.05], p = 0.804.
