Hip complaints differ across age and sex: a population-based reference data for the Hip disability and Osteoarthritis Outcome Score (HOOS)

Background: The Hip disability and Osteoarthritis Outcome Score (HOOS) is a self-administered hip-specific questionnaire intended to evaluate symptoms and functional limitations, and it is commonly used to evaluate interventions in individuals with hip dysfunction or hip osteoarthritis. The HOOS consists of 43 questions in five subscales: Pain, Symptoms, Function in daily living, Function in sport and recreation and Hip-Related Quality of Life. This study aimed to establish population-based reference values for the HOOS and to describe the variation of hip-related symptoms in an adult population. Methods: The HOOS questionnaire was mailed to 840 individuals aged 18-84 years randomly retrieved from a national population record for the Skane region of Southern Sweden. Results: The overall response rate was 67%. Older women and men consistently reported more hip-related complaints than those younger. There were significant differences between the oldest and the youngest age groups in all five subscales in women and men. Conclusions: Hip-related pain, symptoms, activity of daily life and quality of life varied with age and sex in this population-based cohort. Our findings show the importance of using age- and sex-matched reference values for evaluation of outcomes after interventions due to hip-related problems.