Estimation of premorbid intelligence in schizophrenia.

Journal article

To determine whether the National Adult Reading Test (NART) would provide a valid estimate of premorbid intelligence in schizophrenia, two schizophrenic samples were recruited, one consisting of 35 patients resident in long-stay wards, the other of 29 patients normally resident in the community. Schizophrenic patients were individually matched for age, sex, and education with a healthy, normal subject. Both schizophrenic samples scored significantly lower on the Wechsler Adult Intelligence Scale (WAIS) than their respective control groups. NART-estimated IQ did not differ significantly between the community-resident schizophrenics and their controls, suggesting that the NART provides a valid means of estimating premorbid intelligence in such a population. NART-estimated IQ was significantly lower in the long-stay sample than in their controls. Although low NART scores in this latter sample could be a valid reflection of low premorbid IQ, the alternative explanation that NART performance was impaired by onset of the disease cannot be ruled out.

Authors: Crawford, JR; Besson, J; Bremner, M; Ebmeier, K; Cochrane, R

• Journal: British journal of psychiatry : the journal of mental science
• Volume: 161
• Issue: 1
• Pages: 69-74
• Publication date: 1992-07-01
• DOI: 10.1192/bjp.161.1.69
• EISSN: 1472-1465
• ISSN: 0007-1250
• Language: English
• Keywords: Likelihood Functions; Middle Aged; Female; Aged; Intelligence Tests; Reading; Humans; Adult; Male; Schizophrenic Psychology; Intelligence