Validation of the global activity limitation indicator in Taiwan

Abstract

Background: The Global Activity Limitation Indicator (GALI) is a single-item measure of functional decline, it is widely used in Europe but it has never been validated in an Asian population. The aim of this study was to validate the GALI in a sample of older Taiwanese people and to explore whether it captured not only physical but also psychological limitations. Methods: Data for 4961 individuals (mean age, 62.4 ± 9.4 years; 47.2% men) were obtained from a national representative refresh cohort of the 8th wave of the Taiwan Longitudinal Survey on Aging. Logistic regression analysis was used to examine associations among the GALI, activities of daily living (ADLs) and instrumental activities of daily living (IADLs) and to explore whether depressive symptoms (measured by the Center for Epidemiologic Studies Depression Scale, CES-D) could be an indicator of reporting limitations on the GALI. Results: Responding to the GALI, 21.7% of the sample described themselves as 'limited.' In logistic regression, the GALI response was significantly associated with those who reported one or more ADL difficulties (odds ratio [OR] = 35.89, 95% confidence interval [CI] 21.10, 61.03) and IADL difficulties (OR = 13.37, 95%CI 10.09, 17.71), respectively. Furthermore, those with more depressive symptoms were more likely to report they were 'limited' on the GALI. Conclusions: These findings provided evidence that the GALI is a valid tool to assess general limitations in an Asian population. Furthermore, it captured psychological limitations to some extent. There were variations between Taiwan and European countries (as has been previously reported between European countries). The reporting level in the GALI by the Taiwan population was comparatively lower than that in European countries, highlighting the need to embrace cultural differences and to use caution when comparing GALI results across countries.