A symptom checklist and scoring system has been devised which reliably and validly differentiates schizophrenic from non-schizophrenic populations in a number of different types of treatment settings. The scale was developed and refined with 461 case records with the diagnosis of schizophrenia and 211 case records selected to confuse that diagnosis.
87.6 per cent of those diagnosed as schizophrenic scored for schizophrenia by our scale. False positives among the group of non-schizophrenics selected to confuse diagnoses were 15.6 per cent.
Additional positive support for the scale was found by: (1) comparison of each of the individual symptoms used in the scale with the diagnosis of schizophrenia; (2) a cross validational study; (3) a factor analysis; and (4) multiple regression analysis. The scale is easily scored and easily adaptable to computer analysis.