Validity and responsiveness of floor Sitting-Rising Test in Post-Total Knee Arthroplasty- A Cohort Study.

Abstract Objectives To assess the construct validity and responsiveness of floor sitting-rising test (SRT) in individuals with total knee arthroplasty (TKA). Design Cohort study with 6-month follow-up. Secondary analysis using data from a randomized controlled trial. Setting Outpatient rehabilitation research center. Participants All 240 participants enrolled in the parent study who had unilateral primary TKA. Intervention Participants in parent study underwent 12 weeks of exercise programs. Main outcomes Validity analysis correlated baseline data of participants who completed the SRT and measures of knee motion, muscle strength, performance-based tests, and patient-reported outcomes (PROs) of physical and psychosocial function. Responsiveness analysis used the 3- and 6-month follow-up data. Effect sizes were calculated using changes from baseline. Areas under the receiving operating characteristics curve (AUC) were calculated using a global rating of change as the external anchor. Results Of the 240 participants (148 female, age 70±7SD years), 180 (75%) were able to perform the SRT at baseline. Performers scored significantly better in all physical function tests (P Conclusion(s) The results add evidence to the validity of the SRT in patients post-TKA. The strength of the associations suggests that the SRT measures a physical function construct not captured by the other tests. The magnitude of indices of responsiveness for the SRT were similar to other performance-based tests, indicating comparable responsiveness to more widespread tests of functional performance.