Background: The Timed Up and Go test (TUG) is recommended as an evidence-based tool for measuring physical capacity. Instrumented TUG (iTUG) approaches expand classical supervised clinical applications offering the potential of self-assessment for older adults. Objective: This study aimed to evaluate the concurrent validity and test-retest reliability of a smartphone-based TUG self-assessment "up&go app." Methods: A total of 52 community-dwelling older adults (>67 years old) were recruited. A validated and medically certified system attached with a belt at the lower back was used as a reference system to validate the "up&go app" algorithm. The participants repeated the TUG 5 times wearing, a smartphone with the "up&go app" in their front trouser pocket and an inertial sensor to test the concurrent validity. A subsample of 37 participants repeated the "up&go app" measurement 2 weeks later to examine the test-retest reliability. Results: The correlation between the "up&go app" and the reference measurement was r=0.99 for the total test duration and r=0.97 for the 5 single repetitions. Agreement between the 5 repetitions was intraclass correlation coefficient (ICC)=0.9 (0.84-0.94). Leaving out the first repetition, the agreement was ICC=0.95 (0.92-0.97). Test-retest agreement had an ICC=0.79 (0.53-0.9). Conclusions: The duration of 5 repetitions of the TUG test, measured with the pocket-worn "up&go app," was very consistent with the results of a lower-back sensor system, indicating excellent concurrent validity. Participants walked slower in the first round than in the other 4 repetitions within a test run. Test-retest reliability was also excellent. The "up&go app" provides a useful smartphone-based approach to measure 5 repetitions of the TUG. The app could be used by older adults as a self-screening and monitoring tool of physical capacity at home and thereby help to early identify functional limitations and take interventions when necessary.
Böttinger, M.J., Mellone, S., Klenk, J., Jansen, C., Stefanakis, M., Litz, E., et al. (2025). A Smartphone-Based Timed Up and Go Test Self-Assessment for Older Adults: Validity and Reliability Study. JMIR AGING, 8, 1-13 [10.2196/67322].
A Smartphone-Based Timed Up and Go Test Self-Assessment for Older Adults: Validity and Reliability Study
Mellone, SabatoSecondo
Methodology
;
2025
Abstract
Background: The Timed Up and Go test (TUG) is recommended as an evidence-based tool for measuring physical capacity. Instrumented TUG (iTUG) approaches expand classical supervised clinical applications offering the potential of self-assessment for older adults. Objective: This study aimed to evaluate the concurrent validity and test-retest reliability of a smartphone-based TUG self-assessment "up&go app." Methods: A total of 52 community-dwelling older adults (>67 years old) were recruited. A validated and medically certified system attached with a belt at the lower back was used as a reference system to validate the "up&go app" algorithm. The participants repeated the TUG 5 times wearing, a smartphone with the "up&go app" in their front trouser pocket and an inertial sensor to test the concurrent validity. A subsample of 37 participants repeated the "up&go app" measurement 2 weeks later to examine the test-retest reliability. Results: The correlation between the "up&go app" and the reference measurement was r=0.99 for the total test duration and r=0.97 for the 5 single repetitions. Agreement between the 5 repetitions was intraclass correlation coefficient (ICC)=0.9 (0.84-0.94). Leaving out the first repetition, the agreement was ICC=0.95 (0.92-0.97). Test-retest agreement had an ICC=0.79 (0.53-0.9). Conclusions: The duration of 5 repetitions of the TUG test, measured with the pocket-worn "up&go app," was very consistent with the results of a lower-back sensor system, indicating excellent concurrent validity. Participants walked slower in the first round than in the other 4 repetitions within a test run. Test-retest reliability was also excellent. The "up&go app" provides a useful smartphone-based approach to measure 5 repetitions of the TUG. The app could be used by older adults as a self-screening and monitoring tool of physical capacity at home and thereby help to early identify functional limitations and take interventions when necessary.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
