Minimal Clinically Important Difference for PROMIS Physical Function and Pain Interference in Patients Following Surgical Treatment of Distal Radius Fracture

Abstract

We estimated the minimal clinically important difference (MCID) for the Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference (PI) computer adaptive tests (CATs) following surgical treatment of distal radius fracture (DRF). Adult patients surgically treated between November 2017 and November 2020 for isolated DRF were identified. Demographic and patient-reported outcome data were extracted from the electronic health record. Outcomes of interest were the PROMIS PF and PI CATs. Inclusion criteria were met if: (1) PROMIS PF and PI scores were available at preoperative and postoperative visits; and (2) a postoperative clinical anchor question asking about overall response to treatment was answered. An anchor-based MCID estimate was determined by calculating the average absolute score change in PROMIS PF and PI for patients who indicated a mild change to the anchor question. A distribution-based MCID estimate was also calculated using the standard error of measurement and effect sizes of change. The changes in PROMIS PF and PI scores were significantly different between patients who gave responses of much change (n= 73), mild change (n= 51), and no change (n= 19) to the clinical anchor question. The average score changes in the mild change group for PROMIS PF and PI were 5.2 (SD, 3.7) and 6.8 (SD, 4.3) points, respectively, representing the anchor-based MCID estimates. The PROMIS PI anchor-based estimate was moderately correlated with the preoperative score (r=-0.41), time between visits (r=-0.39), and age (r= 0.30). The distribution-based MCID estimates were 3.8 (SD, 1.3) and 3.7 (SD, 1.3) points for the PROMIS PF and PI, respectively. The MCIDs were estimated as 5.2 and 6.8 for the PROMIS PF and PI CATs, respectively, following surgery for DRF. As reports continue to publish a consistent range of MCID values, researchers can be confident in these values and begin using them across a broader spectrum of conditions treated by hand surgeons.