Psychometric evaluation of the Chinese version of the Cornell Scale for Depression in Dementia

Elders with cognitive impairments frequently experience concomitant unidentified depressive symptoms due to an impaired capacity for verbal communication. Therefore, determination of a valid and reliable instrument with which to detect depression in this population requires confirmation through observation. The Cornell Scale for Depression in Dementia (CSDD) has been employed worldwide. However, no formally established psychometric properties have yet been made available for its Chinese version. For this study, we attempted to translate and test the validity and reliability of the CSDD Chinese version (CSDD-C). After completing translation and expert validity, a convenient sample of 145 older adults with dementia was assessed by their caregivers in several care facilities in Southern Taiwan. The CSDD-C was administered to collect data along with the Geriatric Depression Scale short form (GDS-SF). Results found an expert content validity index (CVI) of .92 and concurrent validity between CSDD-C and GDS-SF of .322 (p < .001). The number of factors extracted through our samples is consistent with the original CSDD; inter-rater agreement over a two-week period on each item was significant (Kappa = .43-.89); and the Cronbach's alpha for internal consistency reliability was .84. Results indicate the CSDD-C to be a reliable and valid instrument to help Chinese speaking caregivers determine signs and symptoms of depression in elders with dementia under their care.