Identification of cut-points in commonly used hip osteoarthritis-related outcome measures that define the patient acceptable symptom state (PASS)

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.