Are ratings on the positive and negative syndrome scale for schizophrenia biased by personality traits

The aim of this study was to estimate the potential bias by personality traits for ratings on the Positive and Negative Syndrome Scale (PANSS). Personality dimensions (five factor model), personality traits (SCID-II) and PANSS scores were assessed prospectively in 45 patients with schizophrenia spectrum disorders (SSD). Borderline (r=0.34; p=0.021), avoidant (r=0.66; p Although PANSS positive subscore and PANSS excited component are relatively robust against bias by personality traits, PANSS total score and the remaining subscores are affected to a clinically relevant degree. Outcome studies in SSD patients should control for personality traits.