Targeting Self-Oriented Perfectionism Through a School-Based CBT-Informed Program Integrating Excellencism: A Pilot Study in Final-Year High School Girls.

Adolescent academic pressures may intensify self-critical perfectionistic processes, particularly in senior-secondary cohorts navigating high-stakes transitions. Excellencism has been proposed as an alternative motivational construct, but its viability within school-based interventions remains untested. This pilot examined feasibility, acceptability, and preliminary outcomes of a four-session classroom-delivered CBT-informed program augmented with excellencism principles for final-year girls (N = 80 at baseline). Linear mixed models examined self-oriented perfectionism (SOP) and excellencism as co-primary outcomes, with anxiety, depression, and positive affect as secondary outcomes. SOP showed a small pre-post reduction (d = 0.25) not maintained at follow-up, while excellencism remained stable, consistent with the Scenario 4 preservation pattern of the Juxtaposed Effect Framework. Secondary outcomes were stable. Acceptability indicated modest learning and enjoyment. Without a randomised control, findings are interpreted as preliminary signals. They support integrating CBT with excellencism in school delivery and offer preliminary evidence of a Scenario 4 preservation pattern.