Who benefits from mobile health interventions? A dynamical systems analysis of psychological well-being in early adults.

Research shows that skills for improving Psychological Well-Being (PWB) may be learned through PWB interventions; however, the dynamic mechanisms underlying this learning process are not well understood. Using an Ecological Momentary Intervention (EMI) design, we conducted an 8-week Randomized Controlled Trial (N = 160; aged 18-22 years), implemented in a mobile Health (mHealth) platform to characterize these dynamical mechanisms. College-attending early adults were randomized to three groups: an active control group (N = 55); an intervention group (N = 51) with positive practices intervention; and a second intervention group (N = 54) with positive practices and meditation intervention. The mHealth implementation allowed us to introduce the interventions in participants' daily lives while also assessing their PWB (in terms of positive emotions and relationship quality) several times a day. We used a Bayesian process model to analyze changes in PWB in terms of the underlying dynamical characteristics of change. Findings suggested that the mobile assessment tool itself may have longitudinally improved college-attending early adults' PWB, as evidenced by instances of directional changes in dynamic characteristics (increased within-person mean levels, decreased intra-individual variability, and increased regulation) of PWB measures. Moderation analysis also revealed that people who were low on negative affect improved the most in terms of their mean levels of positive emotions and relationship quality.