Concurrent Validity and Reliability of Video-Based Approach to Assess Physical Function in Adults With Knee Osteoarthritis

Objectives The aim of this study was to determine the concurrent validity and reliability of the Osteoarthritis Research Society International recommended performance-based tests delivered by video-based in adults with knee osteoarthritis.Methods Thirty-two participants (aged 40-70 years; 15 men) undertook assessments of 4 performance-based tests via both video-based (real-time and recorded) and face-to-face approaches, on the same day. Outcome measures were performance-based test and the number of technical issues encountered. The performance-based tests included the 40-Meter Fast-Paced Walk Test (velocity, m/s), the 30-Second Chair Stand Test (number of repetitions), the Stair Climb Test (time, seconds), and the Timed "Up & Go" Test (time, seconds). The Bland-Altman limit of agreement measures, standard error of measurement (SEM), coefficient of variation (CV), minimal detectable changes, and bias (mean difference) were employed to analyze the concurrent validity between video-based and face-to-face approaches of the performance-based tests. Reliability was measured using intraclass correlation coefficients, CV, and SEM.Results A high degree of concurrent validity for the Timed "Up & Go" Test (bias = -0.22), the 30-Second Chair Stand Test (bias = -0.22), the Stair Climb Test (bias = -0.31), and the 40-Meter Fast-Paced Walk Test (bias = -0.06) was found. SEM and CV values were within the acceptable level for concurrent validity. There was a high degree of reliability demonstrated for all tests analyzed. Intraclass correlation coefficient measures ranged from 0.95 to 1.00 for intrarater reliability, and from 0.95 to 0.99 for interrater reliability.Conclusions Video-based assessment of physical performance tests is a valid and reliable tool for measuring physical function among adults with knee osteoarthritis via Microsoft Teams (Microsoft Corp, Redmond, WA, USA).Impact Video-based assessment is a promising public health tool to measure physical function in adults with knee osteoarthritis.