Convergent Validity of the Patient-Reported Outcomes Measurement Information System's Physical Function Computerized Adaptive Test for the Knee and Shoulder Injury Sports Medicine Patient Population

Purpose: To evaluate the convergent validity, precision, and completion times for the Physical Function Computerized Adaptive Test (PF-CAT) in a sports medicine patient population relative to standard measures of knee and shoulder function. Methods: We reviewed all patient visits from April through September 2014 with either knee or shoulder complaints from a university-based sports medicine clinic, during which PF-CAT, Single Assessment Numerical Evaluation (SANE), Simple Shoulder Test (SST), and American Shoulder and Elbow Surgeons (ASES) outcome scores for shoulder patients and PF-CAT, SANE, and International Knee Documentation Committee (IKDC) scores for knee patients were obtained, with an initial visit or one follow-up visit included in the study. Spearman correlation was used to evaluate pairwise agreement among scores. The McNemar chi(2) test was used to evaluate a difference in the number of times floor and ceiling values occurred. Wilcoxon signed rank tests were used to compare differences in completion times. Results: In total, 415 shoulder and 450 knee clinical evaluations qualified for inclusion in the study. A high correlation was found between IKDC and PF-CAT scores (r = 0.75, P <.0001), and a moderately high correlation was found between PF-CAT and both SST (r = 0.68, P <.0001) and ASES (r = 0.63, P <.0001) scores. Maximum differences in the sum of floor-ceiling values versus the PF-CAT were 15% for the SST (P <.0001), 2.5% for the ASES (ceiling only, P =.0133), and 5.8% for the shoulder SANE (floor P =.0012, ceiling P =.0269). The PF-CAT had values of 0.4% for the shoulder and 0.6% for the knee. Zero percent of IKDC scores but 6.9% of knee SANE scores hit floor or ceiling values (floor P =.0019, ceiling P =.0007). The PF-CAT median completion time was lower at 55 seconds versus 268 seconds for the IKDC assessment (P <.0001), whereas shoulder patients' times were 61, 139, and 116 seconds for the PF-CAT, SST, and ASES evaluation, respectively (P <.0001). Conclusions: The PF-CAT showed a high correlation with IKDC scores and a moderately high correlation with ASES and SST outcomes. The PF-CAT takes significantly less time to complete and exhibits improved or similar floor and ceiling effects in comparison to IKDC, SST, and ASES scores. The PF-CAT can be used in evaluating sports medicine knee and shoulder patients. Level of Evidence: Level III, cross-sectional study.