“…The other studies, including: modified Harris Hip Score (mHHS) in three studies,11 35 40 Hip disability and Osteoarthritis Outcome Score (HOOS) in two studies,11 40 Non-Arthritic Hip Score (NAHS) in three studies,31 37 40 Hip Sports Activity Scale (HSAS) in one study,44 Super Simple Hip Score (SUSHI) in one study39 and Western Ontario and McMaster Universities Osteoarthritis Index—12 (WOMAC-12) in one study36 had either no evaluation of their methodological quality concerning content validity specifically for young-aged and middle-aged patients, or a poor rating on this aspect. Furthermore, structural validity was either not assessed, or displayed poor methodology in all these studies, except in the study using WOMAC-12 36.…”