Validity, Reliability, Responsiveness, and Feasibility of the Life-Space Assessment Administered via Telephone in Community-Dwelling Older Adults

Abstract

Abstract Background and Objectives The life-space assessment (LSA) is the most commonly used questionnaire to assess life-space mobility (LSM) in older adults, with well-established psychometric properties for face-to-face (FF) administration. However, these properties have not yet been explicitly studied when the LSA is administered by telephone. The aim of this study was to evaluate the concurrent and construct validity, test–retest reliability, responsiveness, and feasibility of a telephone-based LSA version (TE-LSA) in older adults. Research Design and Methods Fifty community-dwelling older adults (age = 79.3 ± 5.3 years) participated in the study. Concurrent validity was assessed against the FF-LSA construct validity by testing 15 a priori hypotheses on expected associations with LSM determinants, test–retest reliability via 2 telephone surveys 1 week apart, responsiveness after 8.5 ± 1.8 months in participants with improved, stable, and worsened mobility defined by 2 external criteria, and feasibility by the completion rate/time and ceiling/floor effects. Results Good to excellent agreement between the 2 different administration methods was found (intraclass correlation coefficient [ICC2,1] = 0.73–0.98). Twelve of 15 (80%) hypotheses on construct validity were confirmed. ICCs for test–retest reliability were good to excellent (ICC2,1 = 0.62–0.94). Minimal detectable change for the TE-LSA total score was 20 points. Standardized response means were large for worsened (0.88), moderate for improved (0.68), and trivial for stable participants (0.04). Completion rate was 100% and mean completion time was 5.5 ± 3.3 min. No ceiling or floor effects were observed for the TE-LSA total score. Discussion and Implications Telephone administration of the LSA is valid, reliable, responsive, and feasible for assessing LSM in community-dwelling older adults.