Identifying a cut-off point for normal mobility:: a comparison of the timed 'up and go' test in community-dwelling and institutionalised elderly women

Background: physical mobility testing is an essential component of the geriatric assessment. The timed up and go test measures basic mobility skills including a sequence of functional manoeuvres used in everyday life. Objectives: to create a practical cut-off value to indicate normal versus below normal timed up and go test performance by comparing test performance of community-dwelling and institutionalised elderly women. Setting and participants: 413 community-dwelling and 78 institutionalised mobile elderly women (age range 65-85 years) were enrolled in a cross-sectional study. Measurements: timed up and go test duration, residential and mobility status, age, height, weight and body mass index were documented. Results: 92% of community-dwelling elderly women performed the timed up and go test in less than 12 seconds and all community-dwelling women had times below 20 seconds. In contrast only 9% of institutionalised elderly women performed the timed up and go test in less than 12 seconds, 42% were below 20 seconds, 32% had results between 20 and 30 seconds and 26% were above 30 seconds. The 10(th)-90(th) percentiles for timed up and go test performance were 6.0-11.2 seconds for community-dwelling and 12.7-50.1 seconds for institutionalised elderly women. When stratifying participants according to mobility status, the timed up and go test duration increased significantly with decreasing mobility (Kruskall-Wallis-test: p<0.0001). Linear regression modelling identified residential status (p<0.0001) and physical mobility status (p<0.0001) as significant predictors of timed up and go performance. This model predicted 54% of total variation of timed up and go test performance. Conclusion: residential and mobility status were identified as the strongest predictors of timed up and go test performance. We recommend the timed up and go test as a screening tool to determine whether an in-depth mobility assessment and early intervention, such as prescription of a walking aid, home visit or physiotherapy, is necessary. Community-dwelling elderly women between 65 and 85 years of age should be able to perform the timed up and go test in 12 seconds or less.