The Factor Structure for the Geriatric Depression Scale in Screening Depression in Taiwanese Patients with Very Mild to Moderate Dementia

Summary Background To define the factor structures of the 30 items Geriatric Depression Scale (GDS-30) when assessing the depression in patients with very mild to moderate dementia. Methods A total of 240 pairs of patients with very mild to moderate dementia and their caregivers who visited the memory clinic of the medical center in Taiwan from July 2001 to October 2008 were surveyed. The depression of patients with dementia was evaluated using the Chinese version of the GDS-30. We analyzed the factor structure of the GDS with exploratory factor analysis using principle component factor analysis with orthogonal varimax rotation and used the Kaiser-Meyer-Olkin statistic to examine the sampling adequacy. Results The results show a 7-factor model including dysphoria, positive mood, apathy, hopelessness, social withdrawal, decreased concentration, and cognitive impairment. Conclusion The results of this study provide an important reference material and reveal the unobserved variables when using GDS-30 in screening depression of Chinese people with dementia.