Mobile But Connected: Harnessing the Power of Self-Efficacy and Group Support for Weight Loss Success through mHealth Intervention.

Despite the growing popularity of mHealth applications, their usage outcomes have received limited empirical attention. Drawing on server-level user activity data and an online survey (N = 384), this study examines the use of an mHealth application for weight loss to elucidate the ways in which it can help individuals harness the power of self-efficacy and group support to enact behavior change and accomplish their health goals. The results of structural equation modeling based on 6-month user activity data demonstrated that (a) self-efficacy had a positive impact on persistent food logging in an mHealth application; (b) social support received from a mobile group was positively associated with food logging and group participation; and (c) both food logging and group participation predicted weight loss success. Extending these findings, this study suggests theoretical and practical implications for designing individually tailored and evidence-based health intervention strategies using advanced mHealth technologies.