The authors undertook this study so that they might recommend a consensus-derived set of performance-based tests of physical function to be used with patients diagnosed with hip or knee osteoarthritis (OA) or after joint replacement. An international, multidisciplinary expert advisory group was established to guide the study. Possible tests for consideration in the recommended set were identified via a survey of selected experts and through a systematic review of the measurement properties for performance-based tests. A multi-phase, consensus-based approach was used to prioritize and select performance-based tests by applying decision analysis methodology (1000Minds software) via online decision surveys. The recommended tests were chosen based on available measurement-property evidence, feasibility of the tests, scoring methods and expert consensus.
Consensus incorporated the opinions of 138 experienced clinicians and researchers from 16 countries. The five tests recommended by the advisory group and endorsed by Osteoarthritis Research Society International (OARSI) were 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 were recommended as the minimal core set of performance-based tests for hip or knee OA. The OARSI recommended set of performance-based tests of physical function represents the tests of typical activities relevant to patients diagnosed with hip or knee OA and following joint replacements. These 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. The authors also suggested that more research should be directed to expanding the measurement-property evidence of the recommended tests.