Identification of cut-points in commonly used hip osteoarthritis-related outcome measures that define the patient...

To determine patient acceptable symptom state (PASS) estimates in outcome measures commonly used in hip osteoarthritis (OA). Identification of cut-points on commonly used outcome measures associated with patient satisfaction with their current state of health. As part of a randomized controlled trial, 70 patients with a clinical diagnosis of hip OA undergoing a 9-session physiotherapy treatment program completed four physical performance measures and three self-report measures at 9 weeks and 1 year. Upon completion of treatment, patients assessed their current health status according to the PASS question. Cut-points were estimated using receiver operating characteristic curves (anchor-based method), based on the patient's response to the PASS question. At 9 weeks and 1 year, identified cut-points were, respectively, ≤10 and ≤11 for the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale; ≤35 and ≤40 on the WOMAC physical function subscale; ≥+5 and ≥+6 on the global rating of change score; ≤6.05 and ≤5.30 s for the timed-up-and-go; ≤28.3 and ≤24.9 for the 40-m self-paced walk test; ≥11 and ≥12 repetitions for the 30-s chair stand test; and ≥46 repetitions for the 20-cm step test. Initial target cut-points signaling patient satisfaction with their current symptom state following physiotherapy in patients with hip osteoarthritis were determined for seven outcome measures over 1 year.