Crosswalks Between Patient-Reported Outcome Measures After Hip Arthroscopy

BACKGROUND: Hip injuries such as femoroacetabular impingement syndrome (FAIS) and labral tears have become increasingly diagnosed and treated. However, different surgeons have utilized different hip-specific patient-reported outcome (PRO) scores, which makes between-database comparisons difficult. The aim of this study was to develop statistical crosswalks between commonly recorded hip-specific PRO indices for patients undergoing hip arthroscopy for FAIS. HYPOTHESIS: High-fidelity statistical crosswalks would be generated between common hip-specific PROs. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A retrospective study was performed using a large single-institution database from 2014 to 2025. All patients undergoing hip arthroscopy for FAIS with both Hip disability and Osteoarthritis Outcome Score (HOOS) and modified Harris Hip Score (mHHS) at the preoperative, 3-month, 6-month, 1-year, 2-year, and 5-year visits, as well as sex, age, and race data, were included. Equipercentile equating was performed to create statistical crosswalks between the HOOS and mHHS PROs. RESULTS: In this study of 677 patients, equipercentile equating was statistically warranted due to the following assumptions being verified: (1) the scores measured the same underlying construct, with correlation values >0.75; (2) the scores were unidimensional, as demonstrated by an eigenvalue ratio >3; and (3) there was invariance across subpopulations, as demonstrated by a root expected mean squared difference