Content and Cross Validity of the Todai Health Index Depression Scale in Relation to the Center for Epidemiologic Studies Depression Scale and the Zung Self‐rating Depression Scale

Abstract

Content and Cross Validity of the Todai Health Index Depression Scale in Relation to the Center for Epidemiologic Studies Depression Scale and the Zung Self‐rating Depression Scale: Tomoyuki Kawada, et al. Department of Public Health, Gunma University School of Medicine—The validity of the Todai Health Index (THI) depression scale was tested with outpatient data by comparing with a clinical diagnosis based on the DSM III‐R criteria of major depression. The cross validity of the Japanese versions of the CES‐D score and SDS index were also tested in comparison with the THI scale scores of survey data from Japanese female students. The main results obtained were as follows: 1) The sensitivity, specificity, positive predictive value and negative predictive value of the THI depression scale were 0.91, 0.84, 0.86 and 0.89, respectively, and were satisfactory for identifying clinical cases of depression. 2) The CES‐D score and the SDS index showed a high correlation with the THI scale scores, especially with the depression scale of THI. The coefficients of correlation for the THI depression scale and the CES‐D score or SDS index were 0.727 and 0.715, respectively. The partial coefficients of correlation for the THI depression scale and the CES‐D score or SDS index, when the variances of all other scale scores of the THI were kept constant, were 0.528 and 0.536, respectively. 3) Factor analysis was used to compare SDS and CES‐D with 12 THI scales. SDS was related mainly to the psychological complaints and partly related to the physical symptoms. The results indicate that the THI depression scale is valid for use not only in epidemiological surveys but also in monitoring the severity of the depressive state.