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Updated: May 1, 2026

Methodology for Establishing a Community-Wide Life Laboratory for Capturing Unobtrusive and Continuous Remote Activity and Health Data
Published on: July 27, 2018
Life-Space Assessment and Physical Activity Scale for the Elderly: validity of proxy informant responses
James T Cavanaugh1, Kelley Crawford2
1Department of Physical Therapy, University of New England, Portland, ME.
Objective:
To validate the administration of the Life-Space Assessment (LSA) and Physical Activity Scale for the Elderly (PASE) surveys to proxy informants, as would be necessary when measuring long-term outcomes in acutely ill, hospitalized older adults who are initially incapacitated but eventually return to the community.
Design:
Cross-sectional study.
Setting:
General community.
Participants:
Convenience sample of dyads (N=40) composed of an ambulatory older adult and a familiar companion.
Interventions:
Dyads completed the LSA and PASE surveys on 1 occasion. Companions based their responses on the recent mobility and physical activity of the older adult.
Main Outcome Measures:
Paired total scores for each instrument.
Results:
At a group level, the difference between older adult and companion mean scores for each instrument was not significant (P>.05). Standardized mean difference values were small (d<0.1). Paired scores were significantly yet moderately associated: intraclass correlation coefficient(1,1)=.84 to .88; P<.01. Difference in scores was not associated with time spent together (P>.05) or older adult gait speed (P>.05). At an individual level, older adults and companions agreed more closely on the LSA than on the PASE. However, disagreement in excess of estimated measurement error occurred in 40% of the dyads for the LSA and in none of the dyads for the PASE.
Conclusions:
Older adults and companions collectively provided similar responses on each instrument. Nonetheless, varying levels of agreement within individual dyads suggested that proxy responses should be considered carefully. Implications for clinical research and practice research are discussed.

