Validity and sensitivity to change of patient-reported pain and disability measures for elbow pathologies.

Abstract

Prospective cohort study. To evaluate the internal consistency, concurrent construct validity, longitudinal validity, sensitivity to change, and factor structure of the Patient-Rated Elbow Evaluation form (PREE), the patient-reported form of the American Shoulder and Elbow Surgeons Elbow Questionnaire (pASES-e), and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH) in a diverse group of patients who had surgery for various elbow pathologies. Measuring functional outcomes after surgical procedures of the elbow requires valid patient-reported pain and disability questionnaires. The PREE, the pASES-e, and the DASH are commonly used questionnaires. There is, however, insufficient evidence available concerning their validity and sensitivity to change. Data were prospectively collected from 128 patients (mean ± SD age, 46.5 ± 12.8 years) post-elbow surgery. Patients completed the PREE, the pASES-e, the DASH, and the Medical Outcomes Study 36-Item Short-Form Health Survey at baseline (first visit after surgery) and 6 months postsurgery. Concurrent construct validity, longitudinal validity, sensitivity to change, and factor structure were analyzed. Concurrent construct validity was demonstrated by confirmation of expected relationships; the strongest correlations were observed between the PREE pain score, the PREE total score, the pASES-e pain score, and the DASH score (r = 0.73-0.87). The pASES-e function score correlated the least with other constructs. Longitudinal validity demonstrated similar findings: the pASES-e pain change score and PREE change score were most strongly correlated, and the pASES-e function change score and DASH change score were moderately to weakly correlated. All 3 patient-reported questionnaires demonstrated a large effect size and standardized response means greater than 1.0. Structural validity was supported for the PREE (R2 = 77.2%, 4 factors) and the pASES-e (R2 = 74.4%, 4 factors), but not for the DASH (R2 = 71.3%, 5 factors). The PREE, the pASES-e, and the DASH have acceptable validity and sensitivity to change. The pASES-e function subscale is the least sensitive to change and is less correlated to other measures.