Use of questionnaire infeasibility in order to detect cognitive disorders: Example of the Center for Epidemiologic Studies Depression Scale in psychiatry settings

Aim: To examine the extent to which cognitive disorders influenced the feasibility and accuracy of both the 20-item and the 10-item Center for Epidemiologic Studies Depression Scale (CES-D). Methods: Cross-sectional analyses of 223 first-visit patients in a psychiatric clinic and 108 patients in a psychiatric department in a general hospital were conducted. To assess the influence of age, gender, and the presence of cognitive disorders on the feasibility of both versions of the CES-D, multiple logistic regression was performed with feasibility per se as the dummy dependent variable. In order to assess the accuracy of the CES-D, receiver operating characteristic (ROC) analysis was performed. Results: The infeasibility of both types of CES-D were so strongly associated with the presence of cognitive disorders that it can be used as an indicator of cognitive impairment. Moreover, the 10-item CES-D had almost as acceptable an internal consistency reliability as the 20-item CES-D in the study settings. Conclusions: Information obtained from both versions of the CES-D could be utilized fully, using infeasibility as an indicator of cognitive disorders, in psychiatry settings. Other screening instruments with as heavy a cognitive load as the CES-D can also be used in the same manner as an indicator of cognitive disorders to save the need for instruments specifically designed for dementia. Such usage can decrease the burden on both the respondent and the clinician in clinical practice.