Testing the Multilevel Personality-to-Purpose (MPP) framework: An experimental evaluation of an online self-help workbook for promoting purpose in life.

Grounded in the Multilevel Personality-to-Purpose Framework, a six-chapter online self-help workbook was developed to promote purpose in life (purpose) and evaluated in this study. Adult participants (N = 235) recruited from Prolific.ac were randomly assigned to either (a) an experimental condition (completing the workbook in 2 weeks; n = 118) or (b) a waitlist-control condition (n = 117). Assessments were administered on three occasions: preintervention (Time 1), postintervention (Time 2), and 4-week follow-up (Time 3). Linear mixed models partially supported the study hypothesis, indicating that participants in the experimental condition showed greater increases over time in global and state purpose, state meaning, and state hope, relative to the control condition, with small effect sizes. The intervention was also associated with improvements in several indicators of well-being and psychological symptoms; however, these effects were small and not consistently observed across all outcomes or time intervals. Specifically, some outcomes (e.g., state life satisfaction and state suicide ideation from Time 1 to Time 2, as well as state negative affect from Time 1 to Time 3) did not demonstrate Significant Time × Condition interactions. Study findings, along with limitations, future research directions, and practical implications, are discussed. (PsycInfo Database Record (c) 2026 APA, all rights reserved).