Patients with bilateral procedures can be included in total hip arthroplasty research without biasing results.

We explored the influence of bilaterality on the results of a trial of cemented vs uncemented acetabular components. Harris hip scores after 6 months, 2 years, 5 years, and 10 years were analyzed in 240 arthroplasties in 215 patients. Thus, 190 cases in 190 patients were compared to 50 cases in 25 patients.