The factor structure and clinical utility of clinician-rated dimensions of psychosis symptom severity in patients with recent-onset psychosis: Results of a 1-year longitudinal follow-up prospective cohort study

•Early subtype classification may help improving psychosis treatment and long-term prognosis.•We investigated the factor structure of the CRDPSS in patients with recent-onset psychosis.•Factors ‘Psychotic’ and ‘Negative-cognitive’ were extracted and used for classification.•Psychotic- and negative-cognitive patients demonstrate distinct clinical courses. The classic subtype classification of schizophrenia has been removed, and DSM-5 now includes the Clinician-Rated Dimensions of Psychosis Symptom Severity (CRDPSS). In the present study, a factor analysis of the CRDPSS was performed, and we assessed whether patient classification using the derived factor structure helps predict the clinical course. The participants were 390 patients with recent-onset psychosis enrolled in the Korean Early Psychosis Cohort Study (KEPS). Two factors were identified: psychotic (including delusions, hallucinations, disorganization, and abnormal psychomotor behavior) and negative-cognitive (including negative symptoms and impaired cognition). Patients were grouped based on the factor structure and changes in clinical course were monitored over 1 year. The negative-cognitive group demonstrated longer duration of untreated psychosis, earlier onset, and a higher rate of psychiatric comorbidities. Baseline Positive and Negative Syndrome Scale (PANSS) total and Clinical Global Impression-Severity (CGI-S) scores were higher in psychotic group, but group differences were not observed after 2 months. Conversely, the PANSS negative scale score was significantly higher in negative-cognitive group throughout follow-up, and CGI-S score was reversed at 12 months. The findings indicate that the factor structure derived herein for the CRDPSS could be helpful for predicting the clinical course of recent-onset psychosis patients.