Efficacy of psychological interventions in young individuals at ultra-high risk for psychosis: A naturalistic study.

AIM: Early detection and intervention in individuals at risk for developing psychosis have become a priority for many clinical services around the world. Limited naturalistic evidence is available on whether detection and intervention for ultra-high risk (UHR) is effective by means of reducing psychosis risk and improving functioning. METHODS: We compared functioning scores over 5.9 (±7.7) months of time between UHR individuals (n = 61) and help-seeking adolescents without a specific UHR profile (general adolescent help-seeking population [HSP]; n = 82) aged 12 to 25 years receiving psychological interventions at a specialized UHR service in the Netherlands. Attenuated psychotic symptoms (APS) were evaluated over time within the UHR group. In addition, the impact of duration of treatment, <7 sessions, 8 to 21 sessions and >20 sessions, as well as treatment type, that is, cognitive behavioural therapy (CBT) and CBT + add on treatment, were evaluated. RESULTS: Both UHR and HSP showed an increase in functioning over time (P < .001), with no difference between these groups. The UHR group showed a reduction of APS over time (P < .001). More than 20 treatment sessions was more effective than 1 to 6 treatment sessions (P < .01, partial eta squared = .08) and CBT was equally effective as CBT-add on in improving functioning. CONCLUSIONS: The findings of this study suggest that psychological treatment is just as effective in improving functioning in UHR as in HSP. Moreover, it decreases APS in UHR. Improvement in functioning is not affected by treatment type, but positively affected by the duration of treatment.