VALIDATION DATA

An international, multidisciplinary expert advisory group to guide the initial study, and a multi-phase, consensus-based approach was used to prioritize and select performance-based tests. The recommended tests were chosen based on available measurement-property evidence, feasibility of the tests, scoring methods, and expert consensus. The Osteoarthritis Research Society International (OARSI) endorsed the recommended set of five tests, which includes the 30-s chair-stand test, 40 m fast-paced walk test, a stair-climb test, timed up-and-go test, and 6-min walk test. The first three tests were recommended as the minimal core set of performance-based tests for hip or knee OA. The recommended tests are complementary to patient-reported measures and are recommended as prospective outcome measures in future OA research and to assist decision-making in clinical practice.

Test–retest reliability was appropriate; ICC values exceeded 0.70.

For patients with hip OA, good reliability is reported with an intraclass correlation coefficient (ICC) of 0.81 (0.63–0.91). Standard error of measurement (SEM) of 1.27.  MDC90 of 1.6 repetitions in Hip OA (mean age 66.5 SD 9.4 years)