Transcultural adaptation of the Korean version of the Hip Outcome Score.

PURPOSE: The Hip Outcome Score (HOS) is a questionnaire commonly used to assess the clinical outcome of patients after hip arthroscopy. However, a Korean version of the HOS is not available. The aim of this study was to translate and adapt the HOS questionnaire into the Korean language and then assess the psychometric properties of this instrument. METHODS: Translation and transcultural adaptation of the HOS into Korean (HOS-K) was performed in accordance with the international recommendations. Sixty patients (mean age 38.4 years) planning hip arthroscopy participated in evaluating the psychometric properties of the HOS-K. Psychometric analyses consisted of assessing for the following: (1) floor/ceiling effects, (2) internal consistency using Cronbach's alpha, (3) test-retest reliability over 2-3 weeks with intraclass correlation coefficient (ICC), (4) convergent validity by correlation with the SF-36 and Hip disability and Osteoarthritis Outcome Score (HOOS), (5) construct validity by assessing for a difference in HOS-K scores based on a rating of hip function, and (6) responsiveness with a change in score over a 6-month period. RESULTS: The English version of the HOS was translated and adapted to Korean without notable discrepancies. The HOS-K scores were reliable with ICC of 0.946 for the activities of daily living (ADL) subscale and 0.929 for the sports subscale. Internal consistency was confirmed by Cronbach's alpha >0.90 for both subscales. Both subscales had a strong correlation to the five subscales of SF-36, except the general health subscale. The ADL subscale showed strong correlations with all the subscales of the HOOS, and sports subscale showed strong correlations with all subscales of the HOOS, except the symptom subscales of HOOS. The HOS-K also demonstrated evidence for responsiveness without floor and ceiling effects. CONCLUSION: The HOS-K can be recommended as an outcome instrument in hip arthroscopy for Korean-speaking individuals. Surgeons can use the HOS-K to evaluate the outcome of hip arthroscopy in Korea. LEVEL OF EVIDENCE: Therapeutic case series with no comparison group, Level IV.