Minimal clinically important improvement (MCII) and patient-acceptable symptom state (PASS) in total hip arthroplasty (THA) patients 1 year postoperatively

Background and purpose — The increased use of patient-reported outcomes (PROs) in orthopedics requires data on estimated minimal clinically important improvements (MCIIs) and patient-acceptable symptom states (PASSs). We wanted to find cut-points corresponding to minimal clinically important PRO change score and the acceptable postoperative PRO score, by estimating MCII and PASS 1 year after total hip arthroplasty (THA) for the Hip Dysfunction and Osteoarthritis Outcome Score (HOOS) and the EQ-5D. Patients and methods — THA patients from 16 different departments received 2 PROs and additional questions preoperatively and 1 year postoperatively. The PROs included were the HOOS subscales pain (HOOS Pain), physical function short form (HOOS-PS), and hip-related quality of life (HOOS QoL), and the EQ-5D. MCII and PASS were estimated using multiple anchor-based approaches. Results — Of 1,837 patients available, 1,335 answered the preoperative PROs, and 1,288 of them answered the 1-year follow-up. The MCIIs and...