Does realizing strengths, insight, and behavioral practice through a psychological intervention promote personality change? An intensive longitudinal study

The mechanisms of change underlying the effectiveness of personality change interventions are largely unclear. In this study, we used data from a three-month digital intervention with an intensive longitudinal design to test whether a greater realization of general change factors is partly responsible for personality change. Participants ( N = 679, 53.0% female; age: M = 25.3 years, SD = 7.1) seeking to increase either Emotional Stability, Conscientiousness, or Extraversion provided self-ratings on their weekly personality states and the three generic change factors of strengths, insights, and behavioral practice. We found a single-factor structure of change factors within and between individuals. Results showed within-person increases in Emotional Stability, Extraversion, and Conscientiousness states as well as increases in change factors across the intervention. Changes in personality states were coupled with changes in generic change factors. Finally, the results provide initial support for the hypothesis that the realization of general change factors is partly responsible for the effects of the intervention. Within-person increases in the change factors were associated with subsequent increases in Extraversion and Emotional Stability states during the following week. The present findings highlight the need to better understand how and why people change in personality as a result of interventions.