Melissa Johanna Böttinger, Sabato Mellone, Jochen Klenk, Carl-Philipp Jansen, Marios Stefanakis, Elena Litz, Anastasia Bredenbrock, Jan-Philipp Fischer, Jürgen M Bauer, Clemens Becker, Katharina Gordt-Oesterwind
{"title":"A Smartphone-Based Timed Up and Go Test Self-Assessment for Older Adults: Validity and Reliability Study.","authors":"Melissa Johanna Böttinger, Sabato Mellone, Jochen Klenk, Carl-Philipp Jansen, Marios Stefanakis, Elena Litz, Anastasia Bredenbrock, Jan-Philipp Fischer, Jürgen M Bauer, Clemens Becker, Katharina Gordt-Oesterwind","doi":"10.2196/67322","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>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.</p><p><strong>Objective: </strong>This study aimed to evaluate the concurrent validity and test-retest reliability of a smartphone-based TUG self-assessment \"up&go app.\"</p><p><strong>Methods: </strong>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.</p><p><strong>Results: </strong>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).</p><p><strong>Conclusions: </strong>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.</p>","PeriodicalId":36245,"journal":{"name":"JMIR Aging","volume":"8 ","pages":"e67322"},"PeriodicalIF":5.0000,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11951819/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"JMIR Aging","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2196/67322","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GERIATRICS & GERONTOLOGY","Score":null,"Total":0}
引用次数: 0
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.