Compared Halstead-Reitan Battery sccres cf hospitalized male schizophrenics with scores of normals and brain-damaged 8 s to determine performance patterns that differentiate the groups. Schizophrenics performed less well than normals on the Categories, TPT-Memory, and TPT-Location subtests and better than brain-damaged Ss on all subtests except Categories. In general, the effects of medication produced nonsignificant results.
Clinical methods for differentiating between organic and functional disorder remain a principal concern of the clinician and the researcher. To establish valid diagnostic indicators, it generally is agreed that multivariate rather than unidimensional approaches are necessary (Yates, 1966). For this purpose the Halstead-Reitan Battery (H-R Battery) has been recognized as one of the most effective instruments available (Halstead, 1947;Reitan, 1955). I n response to a need to establish more precise patterns for differentiating functional from organic disorders the present study investigated: (1) which subscales of the H-R Battery effectively differentiated schizophrenic patients from organically damaged patients ; and ( 2 ) what confounding effects do drug medication have on the H-R Battery test. performance.
Although there is general consensus that the H-R Battery effectively separates groups of schizophrenic patients from organics, studies have shown a lack of agreement on which specific subtests reflect this difference. Sampling considerations, which have been discussed considerably, may provide some explanation for the variance among studies.
Brain-damaged Ss scored significantly less well than schizophrenic patients on all 11 of the H-R Battery subtests (Vega & Parsons, 1967); however, in a second study, which tested the same hypothesis, three subtests, Categories, Tapping and Rhythm, failed to differentiate the groups (Prigatano & Parsons, 1976). With regard to sampling, the brain-damaged group in the first study was more heterogeneous in that it consisted of CVAs, head trauma and tumor patients, whereas in the latter study most of the patients in the brain-damaged group consisted of head injuries. Watson, Thomas, Anderson, and Fellings (1968) reported an unsuccessful attempt to separate brain-damaged hospitalized patients from schizophrenics by use of the H-R Battery. Only 1 of 24 diagnostic indicators differentiated the groups, which led the authors to conclude that the H-R Battery was of no practical value in such group separations. I n response to these findings Levine and Feirstein (1972) reported that brain-damaged Ss performed more poorly on 8 of 15 H-R subtests. They attributed the failure t o find group differences in the Watson et al. (1968) study to the failure to control for length of hospitalization and consequent chronicity. I n response to this criticism, Watson (1974) claimed that Levine and Feirstein's (1972) positive findings could be attributed to the exclusion of uncooperative patients and particular types of brain-damaged Ss. On the basis of his earlier data Watson reported that when Ss were matched for chronicity no differences between schizophrenic and brain-damaged groups existed, as initially found. Levine (1974) , who criticized the a posteriori matching done by Watson, concluded that the debate 'The authors wish to thank Ralph M. Reitan for his contributions and his permission for the use of his data on brain-damaged and normal Ss.
ZJulie Morrill contributed significantly to the present study by her skilled administration of tests. Reprint requests should be sent to