FACTOR STRUCTURE OF THE GERIATRIC DEPRESSION SCALE IN A COHORT OF DEPRESSED NURSING-HOME RESIDENTS

We examined factor structures of the 30-item Geriatric Depression Scale in a sample of depressed nursing home residents at various levels of cognitive functioning (N = 917; observation-to-variable ratio 30.6:1). Using principal components analysis and orthogonal varimax rotation, a six-factor structure involving 26 of the 30 items was derived. This solution, which explained 55.1% of the variance, consisted of the following factors: life dissatisfaction, dysphoria, hopelessness/decreased self-attitude, rumination/anxiety, social withdrawal/decreased motivation and decreased cognition. This factor solution shows that a screening test for depression like the GDS may be able to make stable and independent distinctions between various dimensions associated with depressed mood in nursing home residents. The factors derived map well onto commonly recognized dimensions of depressed mood in frail older adults residing in long-term care facilities. The proposed six-factor solution offers a stable, intuitively sound and statistically supported framework for differentiation of depressive screening data into independent dimensions. This, in turn, offers opportunities for clinical differentiation in both practice and research efforts using the GDS.