Comparing Methods to Determine the Minimal Clinically Important Differences in Patient-Reported Outcome Measures for Veterans Undergoing Elective Total Hip or Knee Arthroplasty in Veterans Health Administration Hospitals

Abstract

IMPORTANCEThe minimal clinically important difference (MCID) in a patient-reported outcome measure (PROM) is the smallest change that patients perceive as beneficial. Accurate MCIDs are required when PROMs are used to evaluate the value of surgical interventions.OBJECTIVE To use well-defined distribution-based and anchor-based methods to calculate MCIDs in the Hip Disability and Osteoarthritis Outcome Score (HOOS) and in the Knee Injury and Osteoarthritis Outcome Score (KOOS) for veterans undergoing primary total hip arthroplasty or total knee arthroplasty. DESIGN, SETTING, AND PARTICIPANTSA prospective cohort study was conducted of 858 patients undergoing total joint replacement between March 16, 2015, and March 9, 2017, at 3 high-complexity Veterans Affairs Medical Centers.INTERVENTIONS Patients undergoing total hip arthroplasty or total knee arthroplasty were administered HOOS or KOOS PROMs prior to and 1 year after surgery. The Self-Administered Patient Satisfaction Scale (SAPS) for primary hip or knee arthroplasty was administered at 1-year follow-up as an anchor PROM. MAIN OUTCOMES AND MEASURESThe HOOS and KOOS before and 1 year after surgery, change scores (difference between postoperative and preoperative PROM scores), and MCIDs for each measure. For anchor-based methods, receiver operating characteristic curve analysis was performed, including calculation of the area under the curve. RESULTSThe mean (SD) age of the 271 patients who underwent hip arthroplasty was 65.6 (8.3) years, and the mean (SD) age of the 587 patients who underwent knee arthroplasty was 66.1 (8.2) years. There were 547 men in the knee arthroplasty cohort and 256 men in the hip arthroplasty cohort (total, 803 men). There were significant improvements in the mean values of every PROM, with mean (SD) differences greater than 39 for HOOS Joint Replacement (JR) and every hip subscale (HOOS JR, 39.7 [20.2]; pain, 47.6 [20.5]; symptoms, 45.1 [21.5]; activities of daily living, 43.7 [22.1]; recreation, 49.2 [33.5]; quality of life, 50.3 [27.8]) and mean (SD) differences greater than 29 for KOOS JR and every knee subscale (KOOS JR, 30.4 [17.5]; pain, 38.0 [20.4]; symptoms, 29.5 [22.1]; activities of daily living, 34.8 [20.5]; recreation, 34.6 [31.1]; quality of life, 35.2 [26.8]). Different calculation methods yielded a wide range of MCIDs. Distribution-based approaches tended to give lower values than the anchor-based approaches, which gave similar values for most PROMs. Area under the curve values demonstrated good to excellent discrimination for SAPS for nearly all PROMs.CONCLUSIONS AND RELEVANCE Minimal clinically important difference estimates can be highly variable depending on the method used. Patient satisfaction measured by SAPS is a suitable anchor for the HOOS and KOOS. This study suggests that the SAPS-anchored MCID values presented here be used in future studies of total hip arthroplasty and total knee arthroplasty for veterans.

Changes and thresholds in the Forgotten Joint Score after total hip arthroplasty

“…The identified MCID for the FJS may be specific for THA, as a previous study has shown differences in the MCID for THA and TKA when using the same PROM. 31 The style of anchor question used to calculate the MCID has been shown to yield variations in scores, which was also observed in the current study where patient satisfaction was chosen as the anchor. Previous studies have used ‘perceived change’ when calculating the same psychometric measures for the OHS and the OKS.…”

Effects of Protein Supplementation Combined with Exercise Training on Muscle Mass and Function in Older Adults with Lower-Extremity Osteoarthritis: A Systematic Review and Meta-Analysis of Randomized Trials

“…Specifically, walking capability was assessed using walking task outcomes, such as 10-m walk time and timed 6-min walk distance test outcomes. Patient-reported global functioning was assessed using a perceived function scale, such as the Harris Hip Score (HHS) [ 44 ], the Knee injury and Osteoarthritis Outcome Score (KOOS) [ 45 ], and the 36-Item Short-Form Health Survey (SF-36) physical score [ 46 ]. If improved patient condition is indicated by a negative score change for a measure (e.g., pain score and timed up-and-go performance), score changes for that measure had their signs inverted in the meta-analyses.…”

Patient-reported outcome after primary and aseptic revision hip arthroplasty: 1-year follow-up of 3,559 primary and 406 revision THAs in an institutional registry

“…The reported MCII for HOOS are inconsistent ( 20 ). A recent study validated PASS for EQ-5D in hip arthroplasty patients ( 21 ); however, we were not able to find reports on MCII for EQ-5D after THA surgery.…”