Mapping and crosswalk of patient-reported pain measures after surgery in the Michigan surgical quality collaborative registry.

Abstract

Objective: Patient-reported pain is a crucial measure for postoperative recovery, but the correlation between numeric and categorical scales remains unclear. The Michigan Surgical Quality Collaborative (MSQC) used categorical rating scales (CRS) from 2017 to 2020 and 2022, switching to numeric rating scales (NRS) in 2021, offering a chance to compare both.

Methods: We analyzed surgical patients ≥18 years of age across 70 MSQC hospitals. We compared the 2020 CRS regarding pain in the week after surgery with 2021 NRS surgical site (primary outcome) and overall body (secondary outcome) pain questions using modified equipercentile equating. A secondary analysis equated surgical site pain for 2021 NRS and 2022 CRS.

Results: Among 31 362 respondents (55.4 mean age, 57.4% female, 19.5% non-white, 46.6% publicly insured), 81.1% noted "minimal" or "moderate" pain in the 2020 CRS while 76.6% noted surgical site pain scores between 2 through 8 in the 2021 NRS. Responses from surgical site pain NRS were matched to CRS as: 0 = no pain, 1 through 4 = minimal pain, 5 through 8 = moderate pain, and 9 through 10 = severe pain. The mapping of overall body pain NRS was similar except that minimal pain included 0 through 4. The secondary analysis added 21 113 cases confirming these findings.

Discussion: NRS surgical site and overall body pain scores map effectively to the single-question CRS, with pain scores similar over 3 years. This analysis establishes a framework for integrating pain scores across both scales, unlocking their potential to be used as quality postoperative pain measures.