BioPsychoSocial Assessment Tools for the Elderly - Assessment Summary Sheet Test: Global Deterioration Scale (GDS) Year: 1982 Domain: Psychological Assessment Tool Category: Dementia/Alzheimer’s Variations/Translations: Reisberg Scale Setting: Long-term care institutions Method of Delivery: Assessed by formal caregivers Description: The GDS provides caregivers with an overview of the stages of functional decline for those suffering from a primary degenerative dementia such as Alzheimer’s disease. The GDS is comprised of 7 stages, each defined by a set of clinical characteristics. These characteristics are based on dimensions such as memory, learning, communication, sleep, and physical, mental, and social impairment. Scoring/Interpretation: The higher the stage, the more severe the cognitive decline. Stage 1: No cognitive decline (normal function; Stages 2-3: Mild cognitive decline; Stage 4: Moderate cognitive decline; Stage 5: Moderate-severe cognitive decline; Stages 6-7: Severe cognitive decline. Time to Administer: Variable, depending on time required for observation of patient. Availability: Available online through the Alzheimer’s Society (see below), free of charge. Software: N/A Website: www.alzheimer.ca Quantitative/Qualitative: Quantitative Validity (Quantitative): Concurrent validity was established by comparing scores of the GDS to scores from the MMSE (Mini-Mental State Exam) and showed high correlation between the two tools (results reported in Reisberg et al, 1994). Clinical/biological validity was also demonstrated to be satisfactory by comparing GDS results with results from psychometric tests (r = 0.30-0.60), CT scan measures (r = 0.50 for sulcal enlargement and 0.60 for ventricular dilation), and cerebral blood flow (r = 0.70-0.80) (Herndon, 2006). Reliability (Quantitative): Interrater reliability for the GDS was found to be high, ranging from 0.87 to 0.97 in various studies (Herndon, 2006). References: Eisdorfer, C., Cohen, D., Paveza, G., Ashford, J.W., Luchins, D.J., Gorelick, P.B., Hirschman, R.S., Freels, S.A., Levy, P.S., Semla, T.P., & Shaw, H.A. (1992). An Empirical Evaluation of the Global Deterioration Scale for Staging Alzheimer’s disease. The American Journal of Psychiatry, 149, 190-194. Herndon, R.M. (2006). Handbook of Neurologic Rating Scales (2nd ed.). New York: Demos Medical Publishing. Reisberg, B., Ferris, S.H., Leon, M.J., & Crook, T. (1982). The Global Deterioration Scale for assessment of primary degenerative dementia. American Journal of Psychiatry, 139, 1136-1139. Comments: N/A