INTERRATER RELIABILITY OF THE NEUROLOGICAL EXAMINATION IN SCHIZOPHRENIA

Neurological Examination Abnormalities (NEA) are prevalent in schizoph renia, but the significance of this is obscured by methodological prob lems. The Neurological Evaluation Scale (NES), the most widely used st ructured neurological examination in schizophrenia research, has had l imited study of its inter-rater reliability (IRR). An augmented versio n of the NES was jointly administered (one examiner-rater and one obse rver-rater) by three pairs of psychiatrists to two populations of pati ents with idiopathic psychotic disorders. In addition to the ordinal a nd categorical data yielded by the original NES, continuous data were recorded in one of the series. Reliability analyses of our populations and a previously published study, reveal consistently adequate IRR in 12 of the 26 items assessed, and inconsistently adequate IRR in an ad ditional 11. Consistent with studies using other NEA schedules, IRR wa s unacceptably low for some items that rely on subjective severity rat ings. Certain rare abnormalities, which posed difficulties for the est imation of IRR, are probably not generally useful in the study of schi zophrenia. Reliability estimates of continuous, ordinal and dichotomou s data were comparable in most cases. We recommend that certain items from the NES be deleted, and that other studies of NEA in psychiatry f ollow similar procedures before undertaking further analyses. (C) 1998 Elsevier Science B.V.