Survey mode influence on patient-reported outcome scores in orthopaedic surgery: telephone results may be positively biased.
Abstract: Patient-reported outcome (PRO) scores are used to evaluate treatment modalities in orthopaedic surgery. The method of PRO collection may introduce bias to reported surgical outcomes due to the presence of an interviewer. This study evaluates post-operative PROs for variation of outcomes between survey methods-in-person, online, or telephone.
Methods: From 2008 to 2011, 456 patients underwent arthroscopic surgical treatment for acetabular labral tears. All pre-operative surveys were completed in the clinic during pre-operative visit. Two-year follow-up questionnaires were completed by 385 (84 %) patients. The PRO data were prospectively collected pre- and post-operatively using five tools: modified Harris Hip Score (mHHS), Hip Outcome Score Activities of Daily Living (HOS-ADLS), Hip Outcome Score Sports-Specific Subscale (HOS-SSS), Non-Arthritic Hip Score (NAHS), and visual analog scale. Patients were grouped according to method of 2-year follow-up: in-person during follow-up visit (102 patients, 26 %), online by email prompt (138 patients, 36 %), or telephone with an interviewer (145 patients, 38 %).