Translation and Cross-cultural adaptation process of the Osteoarthritis Knee and Hip Quality of Life questionnaire. According to granted guidelines, shared by the developer of the questionnaire, the study was conducted among Hungarian patients affected by osteoarthrosis.

This prospective study was performed among patients diagnosed - by the doctors acting as the expert panel of this study - with OA of the lower limb. The recruitment period was: June 2017 and November 2017, in six hospitals situated in six different geographical regions of Hungary. The participating hospitals were selected in a way to represent different geographic and cultural areas of the country; the patients were selected randomly by the doctors of the given sites. The process was conducted with the contribution of: (1) Translation committee (4 members), (2) Our research team, as moderator (4 members), (3) Expert panel (6 doctors professors of the study sites: orthopaedists, rheumatologists, musculoskeletal rehabilitation doctors). The used instruments were for the validation process: Short version of World Health Organization Quality of life questionnaire (WHOQoL-BREF), EuroQuality of Life - 5-dimension questionnaire as generic quality of life measurement tools (EQ-5D - VAS). In addiction 99 patients filled the questionnaires in an appropriate way. The results were evaluated by 23.0 version of SPSS program.

Inclusion Criteria:

• age over 18 years
• clinically/doctor diagnosed knee and/or hip osteoarthritis
• native Hungarian language
• ability of self-filling and completely filled patient data sheet.

Exclusion Criteria:

• age under 18 years
• other type of OA osteoarthritis
• psychiatric disorders
• surgeries within 1 month
• incapable of filling out the forms/tools

Both sex, above 18 years old