How stages of change and need for reflection can inform the design of persuasive digital health interventions for obesity management

Abstract The integration of technology offers opportunities to use persuasive systems for promoting behavior change and tackling obesity, a critical global health issue. The Persuasive Systems Design (PSD) framework offers strategies and features that can be systematically applied to digital interventions. However, it remains unclear which system characteristics and user characteristics interact in influencing health outcomes. This study investigates how user’s perceptions of PSD features (system characteristics), interact with crucial user characteristics, namely, Stages of Change (SOC), and Need for Reflection (NFR), to influence waist circumference reduction after six months of utilizing a mobile health behavior change support system. Data from 96 participants in a randomized controlled trial were analyzed after six months of mobile health behavior change support system use. Partial Least Squares Structural Equation Modeling was employed. SOC explained 22.2% of waist circumference reduction variance. Furthermore, users who perceived a system as highly persuasive were more likely to progress through SOC ( R 2 = 0.119). Among PSD features, Dialogue Support and Primary Task Support explained 55% of the variance in perceived persuasiveness. Additionally, both Dialogue Support and Credibility Support had a mutual effect on Primary Task Support ( R 2 = 0.688). Finally, the user’s NFR explained 11.3% of the variance in dialogue support. The out-of-sample predictive power supports the reliability of the model's findings. The model's robustness in showing that SOC can predict waist circumference decrease highlights the potential for better-customized mobile health behavior change support system solutions. Tailoring interventions to individuals' SOC enables personalized, effective behavior change, aligning with their readiness and improving success rates.