Supporting Early Career Development Through Volitional Personality Change: A Multi-Layered Evaluation of a Digital Intervention

Personality change interventions (PCIs) offer promising opportunities for personal development, yet little is known about how different psychological layers of personality—thoughts, feelings, behaviors, skills, and identity—respond to intentional change efforts. This study addressed that question through a six-week smartphone-based intervention tailored to students' preparation for entering the workforce, an applied setting in which PCIs remain understudied. Final-year undergraduate clinical psychology students (N = 565) participated in one of three interventions designed to enhance resilience, social boldness, or punctuality, with a quasi-experimental control group for comparison (N = 99). Participants in all three conditions showed meaningful growth in the targeted facet, with gains exceeding changes in non-targeted facets, surpassing those observed in the control group, and persisting at the four-week follow-up. Moreover, perceived feasibility of change moderated intervention effectiveness. Finally, participants targeting resilience and social boldness showed significant growth across psychological layers, whereas those targeting punctuality changed primarily in the behavioral and skill layers. The identity layer—representing how participants see themselves—exhibited the smallest degree of change. Collectively, these findings enrich volitional personality change (VPC) theory by illuminating how personality change unfolds across different psychological layers, while also demonstrating the feasibility of PCIs in supporting the school-to-work transition.