Measuring life-space mobility in community-dwelling older adults.
OBJECTIVE
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.


METHODS
Prospective, observational cohort study.


METHODS
Five counties (three rural and two urban) in central Alabama.


METHODS
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.


METHODS
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.


CONCLUSIONS
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.
Baker
Patricia S
PS
Department of Sociology Center for Aging, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA. pbaker@uab.edu
Bodner
Eric V
EV
Allman
Richard M
RM
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003196:Computer Graphics; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008124:Locomotion; D008297:Male; D009043:Motor Activity / Q000502:physiology; D011446:Prospective Studies; D015203:Reproducibility of Results