Overview
A validation study comparing smartphone-instrumented Timed Up and Go assessments against traditional stopwatch administration, reporting strong agreement plus additional sub-phase metrics.
The Timed Up and Go (TUG) test is one of the most widely used functional mobility assessments: a person stands from a chair, walks three meters, turns, returns, and sits, while a clinician times the whole sequence. This study evaluated whether a smartphone-instrumented version produces results consistent with traditional stopwatch administration.
In the studied cohort, participants performed TUG tests measured simultaneously by trained raters with stopwatches and by the Sentinel smartphone application. The study reported strong agreement between the two methods, with differences within clinically acceptable ranges for the population assessed.
Beyond replicating the total time, the instrumented version decomposed the test into sub-phases — sit-to-stand duration, walking segments, turn time, and stand-to-sit — which stopwatch administration cannot separate. In the study, these sub-phase metrics revealed differences between participants with similar total times, suggesting additional discriminative information for clinical review.
The authors note the usual limitations: results reflect the studied population and setting, and instrumented measures are intended to support, not replace, comprehensive clinical evaluation by qualified professionals. Within those bounds, the findings support smartphone-based TUG as a consistent, information-rich alternative to manual timing.
Key Takeaways
- Smartphone TUG timing showed strong agreement with stopwatch measurement in the studied cohort
- Sub-phase decomposition adds information a stopwatch cannot capture
- Similar total times can hide different movement profiles
- Findings apply to the studied population; clinical evaluation remains essential