Objective PANSS‐8 and PANSS‐6 are derived from the 30‐item Positive and Negative Syndrome Scale (PANSS‐30). We investigate whether PANSS‐8 or PANSS‐6 is a reliable, valid, sensitive to change measure, and scalable, and whether early improvement using them can predict response/remission. Method Data were from 3 trials for 270 schizophrenia inpatients receiving antipsychotics. Internal consistency, validity, sensitivity to change, and scalability using PANSS‐30, PANSS‐8, and PANSS‐6 at each assessment were examined. Early improvement was defined as at least 20% reduction of PANSS‐30, PANSS‐8, or PANSS‐6 scores at week 2. Response was defined as at least 40% reduction of PANSS‐30 and remission as a score of PANSS‐8 ≤ 3 on each item at endpoint. Receiver operating characteristic analysis was used to determine which rating scale had better discriminative capacity. Results PANSS‐8 and PANSS‐6 showed acceptable internal consistency, were highly correlated with PANSS‐30, and had sensitivity to change. PANSS‐8 and PANSS‐6 were scalable at each assessment, except for PANSS‐6 at baseline. Early improvement using PANSS‐8 or PANSS‐6 had comparable predictive values with that of PANSS‐30 for response/remission. Conclusion PANSS‐8 and PANSS‐6 are clinically useful measures. Early improvement, regardless of whether PANSS‐30, PANSS‐8, or PANSS‐6 is used, is a statistically significant predictor of response/remission.