Measuring Life-Space Mobility in Community-Dwelling Older Adults

Objectives: To evaluate the validity and reliability of a standardized approach for assessing life‐space mobility (the University of Alabama at Birmingham Study of Aging Life‐Space Assessment (LSA)) and its ability to detect changes in life‐space over time in community‐dwelling older adults. Design: Prospective, observational cohort study. Setting: Five counties (three rural and two urban) in central Alabama. Participants: Community‐dwelling Medicare beneficiaries (N=306; 46% male, 43% African American) who completed in‐home baseline interviews and 2‐week and 6‐month telephone follow‐up interviews. Measurements: The LSA assessed the range, independence, and frequency of movement over the 4 weeks preceding assessments. Correlations between the baseline LSA and measures of physical and mental health (physical performance, activities of daily living, instrumental activities of daily living, a global measure of health (the short form‐12 question survey), the Geriatric Depression Scale, and comorbidities) established validity. Follow‐up LSA scores established short‐term test‐retest reliability and the ability of the LSA to detect change. Results: For all LSA scoring methods, baseline and 2‐week follow‐up LSA correlations were greater than 0.86 (95% confidence interval=0.82–0.97). Highest correlations with measures of physical performance and function were noted for the LSA scoring method considering all attributes of mobility. The LSA showed both increases and decreases at 6 months. Discussion: Life‐space correlated with observed physical performance and self‐reported function. It was stable over a 2‐week period yet showed changes at 6 months.