To compare levels of disability of people with and without hip and knee arthroplasty in a random national sample.
In 1999 a screening questionnaire to classify people into groups of increasing probabilities of disability was sent to 417 500 people; response rate 86%. The study population was obtained by a stratified randomisation, with a high sampling rate for the most severely disabled group and a minimum sampling rate for people without daily living restrictions. A computer assisted interview to assess levels of disability, dependence, and handicap was given to 21 760 people; response rate 78%. A weighting factor was applied to obtain estimates representative of the French population. The presence of chronic conditions, impairments, and disability was ascertained from the subjects' reports.
The hip and knee arthroplasty group comprised 815 subjects in the sample, indicating an estimated 691 000 subjects (95% confidence interval (CI) 597 000 to 785 000) in the French non-institutionalised population. The prevalence of arthroplasty is estimated at 1.2%. After adjustments for confounding factors, activity limitations were greater among subjects with arthroplasty for the following activities: climbing stairs (odds ratio (OR)=4.0, 95% CI 2.8 to 5.8); walking distance (OR=3.4, 95% CI 2.5 to 4.6 for a walking distance less than 500 m); bending forward (OR=3.2, 95% CI 2.2 to 4.7); cutting toenails (OR=2.8, 95% CI 1.9 to 3.9); carrying (OR=2.6, 95% CI= 1.8 to 3.8); shopping (OR=2.1, 95% CI 1.5 to 2.9).
This study would be useful to policy-makers considering population strategies for managing disabling arthritis.