Comparing PANSS-6 and PANSS-30 for clinical and functional outcomes in first-episode psychosis: A 2-year follow-up in a Spanish cohort

Assessing clinical symptoms in First Episode Psychosis (FEP) is essential for guiding treatment decisions and predicting outcomes. The Positive and Negative Syndrome Scale (PANSS-30) is widely used for this purpose; however, its length limits feasibility in routine clinical practice. The PANSS-6, a shorter version, represents a promising alternative, though its performance in FEP populations remains underexplored. This study evaluated the predictive abilities of PANSS-30 and PANSS-6 for clinical remission, functional remission, and relapse over a 2-year follow-up in a Spanish cohort of 193 FEP patients. Data were derived from the PEPs Project, with PANSS30 assessments conducted at baseline and at 2, 6, 12, and 24 months; PANSS-6 scores were calculated from PANSS-30 at the same visits. Clinical remission, functional remission, and relapse were defined using established criteria. Logistic regression and ROC-AUC analyses assessed predictive and discriminatory performance. Agreement between the Remission in Schizophrenia Working Group (RSWG) for PANSS-30 and PANSS-6 remission criteria was near-perfect at 1 and 2 years (kappa >= 0.98). PANSS-6 demonstrated stronger predictive associations and similar discriminatory performance to PANSS-30 for clinical and functional remission, while its performance for relapse over two years was similar. In conclusion, the PANSS-6 is a reliable and efficient tool for assessing clinical outcomes in FEP, offering similar predictive accuracy to PANSS-30 while being more practical for routine use due to its shorter administration time.