The convergence of neuro psychological testing and clinical ratings of cognitive impairment in patients with schizophrenia

This study examined the relationship between clinical rating of cognitive s ymptoms and performance on neuropsychological tests in acute and chronic sa mples of patients with schizophrenia. Two separate studies examined: patien ts who Varied widely in their lifetime functional outcome, including 263 el derly poor-outcome inpatients and 20 acutely admitted patients. In the firs t study, six cognitive performance measures were collected, and in: the sec ond study, five different measures were collected. Correlations with differ ent symptom models of cognitive and negative symptoms were examined. in bot h samples, cognitive symptoms were never more highly correlated with cognit ive test performance than with negative symptoms. When cognitive and negati ve symptom ratings were combined, they never accounted for as much as half of the variance in performance on the cognitive tests in both samples. Thes e data suggest that clinical assessment of symptoms is not a viable alterna tive to neuropsychological testing to obtain information about cognitive fu nctioning in schizophrenia. These results may also be specific to the clini cal rating scale used, the Positive and Negative Syndrome Scale (PANSS). Co pyright (C) 2001 by W.B. Saunders Company.