Abstract
BACKGROUND: Early psychosis and schizophrenia-spectrum disorders are life-altering conditions, frequently associated with persistent impairments in functioning. Although evidence-based interventions exist, treatment outcomes remain variable. Self-Determination Theory (SDT) posits that autonomy-supportive environments facilitate positive outcomes; however, mediators of this association have been understudied in treatment settings of this clinical population. STUDY DESIGN: Data were drawn from the Recovery After an Initial Schizophrenia Episode-Early Treatment Program study, a multisite, cluster-randomized controlled trial comparing NAVIGATE (n = 223; 78% male; Mage = 23.18), a coordinated specialty care intervention informed by SDT principles, to community care (CC; n = 180; 66% male; Mage = 23.08). Structural equation modeling was used to test whether perceived autonomy support from healthcare providers predicted overall functioning indirectly through recovery-oriented psychological growth. Models were evaluated separately by treatment condition and by study year, adjusting for baseline group differences. STUDY RESULTS: Model fit indices indicated adequate fit (RMSEA≤.05, CFI > .95, SRMR<.08, TLI > .95). Among NAVIGATE participants, perceived autonomy support at 3 months predicted functioning at 12 months via recovery-oriented psychological growth processes at 6 months (ß = 1.41, SE = 0.73, abps = 0.063, 95%CI, 0.32-3.05); this indirect effect remained significant at Year 2. Significant full mediation effects were observed. No indirect effects were detected in the CC group. CONCLUSIONS: Treatment programs that emphasize autonomy-supportive principles, such as NAVIGATE, lead to improved functional outcomes by fostering recovery-oriented psychological growth. These findings highlight the relevance of SDT in clinical practice, providing a framework to optimize treatment outcomes by cultivating autonomy-supportive environments.