Mohammad H Ebrahimzadeh - Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences , Ahmad-abad St,Mashhad, ۹۱۷۹۹-۹۱۹۹ Iran
Hadi Makhmalbaf - Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences , Ahmad-abad St,Mashhad, ۹۱۷۹۹-۹۱۹۹ Iran
Ali Birjandinejad - Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences , Ahmad-abad St,Mashhad, ۹۱۷۹۹-۹۱۹۹ Iran
Farideh Golhasani keshtan - Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences , Ahmad-abad St,Mashhad, ۹۱۷۹۹-۹۱۹۹ Iran
Hosein Asghar Hoseini - Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences , Ahmad-abad St,Mashhad, ۹۱۷۹۹-۹۱۹۹ Iran
Seyed Mahdi Mazloumi - Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences , Ahmad-abad St,Mashhad, ۹۱۷۹۹-۹۱۹۹ Iran

  Background: Osteoarthritis of the knee is the most common chronic joint disease that involves middle aged and elderly persons. There are different clinical instruments to quantify the health status of patients with knee osteoarthritis and one example is the WOMAC score that has been translated and adapted into different languages. The purpose of this study was cultural adaptation, validation and reliability testing of the Persian version of the WOMAC index in Iranians with knee osteoarthritis.   Methods: We translated the original WOMAC questionnaire into Persian by the forward and backward technique, and then its psychometric study was done on ۱۶۹ native Persian speaking patients with knee degenerative joint disease. Mean age of patients was ۵۳.۹ years. The SF-۳۶ and KOOS were used to assess construct validity. Results: Reliability testing resulted in a Cronbach’s alpha of ۰.۹۱۷, showing the internal consistency of the questionnaire to be a reliable tool. Inter-correlation matrix among different scales of the Persian WOMAC index yielded a highly significant correlation between all subscales including stiffness, pain, and physical function. In terms of validity, Pearson`s correlation coefficient was significant between three domains of the WOMAC with PF, RP, BP, GH, VT, and PCS dimensions of the SF-۳۶ health survey (P<۰.۰۰۵) and KOOS (P <۰.۰۰۰۱) .   Conclusions: The Persian WOMAC index is a valid and reliable patient- reported clinical instrument for knee osteoarthritis.

Iranian version, Knee Osteoarthritis, KOOS, Persian, Reliability, Validity, WOMAC