Content Validity and Reliability of the Persian Version of the Forgotten Joint Score Questionnaire in Patients Undergoing Total Hip Arthroplasty

Forgotten Joint Score (FJS) is a patient-reported outcome measurement that evaluates patients' ability to forget the replaced joint (knee or hip) in everyday activity. This study aimed to evaluate the validity and reliability of the Persian version of this questionnaire in Iranian patients who underwent total hip arthroplasty. A team of specialists reviewed this questionnaire and voted for its clarity and content validity. Then, the FJS was filled out by 100 randomly selected total hip arthroplasty patients between 2019 and 2021 with at least 6 months of follow-up. The reliability coefficient (Cronbach's alpha) was calculated. A total of 95 patients who met the inclusion criteria, with the mean age 59.9 ± 11.6 years and 26.6% being female, participated in the study. Patients had no difficulty with the content and linguistic format of the Persian FJS-12. The mean FJS for these patients was 50.8 ± 4.6. The Cronbach's alpha was measured at 0.87. The mean content validity index was 0.93. FJS-12 can discriminate even patients with eximious pain and functional outcomes after joint reconstruction surgery. The Persian format of FJS-12 showed acceptable internal consistency using Cronbach's alpha and acceptable content validity. Therefore, it can be utilized in the Iranian population for future research studies.