A meta-analysis of the factor structure of the Geriatric Depression Scale (GDS): the effects of language.

ABSTRACT

BACKGROUND: Given the lack of consensus on the factor structure of the Geriatric Depression Scale (GDS), as well as the fact that the GDS factor structure appears to vary across diverse cultural and/or language groups, the present meta-analysis examined whether the factor structure of the GDS varies by language. METHODS: A total of 26 published studies using exploratory factor analysis (14,669 participants; 10 languages) were included in the meta-analysis. The factor structure of the GDS was assessed in the overall sample as well as in each language that had been examined in at least two different studies. RESULTS: The analysis of the full sample resulted in a four-factor structure, whereas analyses of the individual languages produced structures with 4 to 6 factors. The mean variable cosines between languages ranged from 0.612 to 0.839, suggesting that the different languages produced distinct factor structures. The three factors of dysphoria, social withdrawal-apathy-cognitive impairment, and positive mood were commonly observed across different languages. Of these, the positive mood factor was the most similar across the languages. CONCLUSIONS: These results provide strong evidence of language differences in the factor structure of the GDS. The findings suggest a need for researchers and clinicians to be careful when administering the GDS in different languages, as well as a need to take structural differences into account when interpreting results of the GDS.