Feasibility and Validity of a Remotely Administered 30-Second Sit-to-Stand in People with Multiple Sclerosis.

Abstract

To evaluate the feasibility and validity of the remotely administered 30-second Sit-to-Stand (30s STS) test as a measure of lower-extremity function in a convenience sample of people with multiple sclerosis (MS). Cross-sectional observational study. Remote, videoconference-based assessments conducted via Zoom. Convenience sample of adults with MS (n=541) and healthy controls (n=74). Not applicable. Number of 30s STS repetitions, completion rate, and correlations of 30s STS performance with cognitive and patient-reported outcome measures. The remote 30s STS test was completed by 498 participants with MS (92%) and all 74 healthy controls (100%) with no adverse events. The 30s STS performance was significantly lower in the MS than in healthy controls (10.4 vs 14.0 repetitions; P<.001; d=-0.75), and this group difference remained significant after adjusting for group differences in age, sex, and marital status. The 30s STS repetitions were strongly associated with mobility disability (patient-determined disease step: r=-0.56) and walking limitations (12-Item Multiple Sclerosis Walking Scale: r=-0.57); moderately associated with physical health (12-Item Short Form Health Survey Physical Component Summary: r=0.41) and processing speed (Symbol Digit Modalities Test: r=0.34); and weakly associated with symptoms, mental status, verbal learning and memory (California Verbal Learning Test-Second Edition), and physical activity in MS. The remotely administered 30s STS appears to be a feasible and valid measure of lower-extremity physical function in stable, relapse-free individuals with MS and may be a useful outcome for telerehabilitation research in this population.