Schizophrenia Research, 3 (1990) 241- 25 1 Elsevier 241 SRS 00110 A depression rating scale for schizophrenics Donald Addington’, Jean Addington and Bernard Schisse13 1 University zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA of Calgary , Department of Psychiatry, Foothills Hospital, 1403 29th St. N. zyxwvutsrqponmlkjihgfedcbaZYXWVU W., Calgary, N. W. T2N 2T9, Canada, =Holy Cross Hospital, 2210 2nd Street S. W ., Calgary, AB T2S IS6, Canada, and 3Department of Sociology, University of Saskatchew an, Saskatoon, Saskatchew an, Canada Scales for assessing depression are well developed for non-psychotic populations but have been criticized for being inappropriate for psychotic populations. As a result we have developed a new rating scale for the measurement of depression in schizophrenia based on items selected from the Hamilton Depression Rating Scale and the Present State Examination. The selection was based on a three stage procedure first factor analysis then measures of internal consistency and finally face validity. Ratings of depression were made on 50 acutely ill schizophrenics meeting DSM-III criteria for schizophrenia assessed at two points in time. Our results indicate that several items from both scales form a superior instrument for measuring depression in schizophrenia. The eleven items generated a Cronbach’s alpha of 0.84 at time one and 0.89 at time 2. Key waords: Depression; (Schizophrenia) INTRODUCTION The increasing attention paid to the negative symp- toms of schizophrenia in the last decade has brought about the development of a number of negative symptom rating scales (Andreasen, 1982; Lewine et al., 1983; Heinrichs et al., 1984; Iager et al., 1985; Kay et al., 1987). During the same period there has been increasing attention given to depres- sion in schizophrenia because of its significance for diagnosis, treatment and outcome (McGlashan and Carpenter 1976; Knights et al., 1981; Hirsch, 1982; Mandel et al., 1982; Johnson, 1986; Bland, 1987; Siris et al., 1987). However there are a number of difficulties associated with the assess- ment of depression in schizophrenia. These include the temporal variability of depressive syndromes (Knights et al., 1979; Siris et al., 1984, 1986; Craig et al., 1985) the poor correlation between self- report and observer reports of depression (Craig Correspondence to: D. Addington, University of Calgary, Department of Psychiatry, Foothills Hospital, 1403 29th St, N.W., Calgary, N.W. T2N 2T9, Canada. and Van Natta, 1976; Brown et al., 1979), and the possible overlap with extrapyramidal syndromes (Rifkin et al., 1975; Van Putten and May, 1978) and negative symptoms (Prosser et al., 1987). The full range of depression rating scales used to assess depression in non-psychotic populations has been used in studies of depression in schizophrenia. Despite the finding that patterns of depression in outpatient schizophrenics resemble those in other depressed groups (Weissman et al., 1977) compar- isons of different rating scales on the same patients suggest that these scales may measure different dimensions in schizophrenic patients than they do in patients with affective disorders (Craig et al., 1985; Addington and Addington, 1989). Finally different measures of depression appear to be more congruent in the post-psychotic phase of the dis- order than in the acute phase of the disorder (Addington and Addington, 1989). The present study was undertaken to derive a new rating scale for depression in schizophrenics which would be useful for assessing levels of depression in this population. The internal reliabil- ity of the scale is compared to two existing scales at two stages of the disorder. 0920-9964/90/$03.50 G 1990 Elsevier Science Publishers B.V. (Biomedical Division)