Assessments of Life-space Mobility (LSM) evaluate the locations of movement and their frequency over a period of time to understand mobility patterns. Advancements in and miniaturization of GPS sensors in mobile devices like smartwatches could facilitate objective and high-resolution assessment of life-space mobility. The purpose of this study was to compare self-reported measures to GPS-based LSM extracted from 27 participants (44.4% female, aged 65+ years) who wore a smartwatch for 1-2 weeks at two different site locations (Connecticut and Florida). GPS features (e.g., excursion size/span) were compared to self-reported LSM with and without an indicator for needing assistance. Although correlations between self-reported measures and GPS-based LSM were positive, none were statistically significant. The correlations improved slightly when needing assistance was included, but statistical significance was achieved only for excursion size (r=0.40, P=0.04). The poor correlations between GPS-based and self-reported indicators suggest that they capture different dimensions of life-space mobility.

The authors have declared no competing interest.

This study was funded by the National Institute on Aging Claude D. Pepper Older American Independence Center NIH/NIA U24AG059624 and the National Institute on Aging P30AG021342 (Gill, Hajduk). Dr. Smail was funded on the T32AG062728 Translational research on aging and mobility (TRAM) program.

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This study was approved by the University of Florida institutional review board and Yale University institutional review board.

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