Citation

Wan V, Reddy S, Thomas A, Issa N, Posluszny J, Schwulst S, Shapiro M, Alam H, Bilimoria KY, Stey AM. J. Trauma Acute Care Surg. 2022; ePub(ePub): ePub.

Copyright

(Copyright © 2022, Lippincott Williams and Wilkins)

DOI

10.1097/TA.0000000000003656

PMID

35647796

Abstract

BACKGROUND: Injury severity score (ISS) is a measurement of injury severity based on the Abbreviated Injury Scale (AIS). Due to the difficulty and expense of AIS coding, there have been recent efforts in mapping ISS from administrative International Classification of Disease (ICD) codes instead. Specifically, the open source and freely-available International Classification of Diseases Programs for Injury Categorization in R (ICDPIC-R) converts ICD-9 codes to ISS. This study aims to compare ICDPIC calculations versus manually derived TQIP calculations for ICD-10 codes. Moderate concordance was chosen as the hypothetical relationship due to previous work by both Fleischman et al. who found moderate to substantial concordance between ICDPIC and ISS as well as DiBartolomeo et al. who found none to slight concordance. Given these very different findings, we thought it reasonable to predict moderate concordance with the use of more detailed ICD-10 codes.

METHODS: This was an observational cohort study of 1,040,728 encounters in the Trauma Quality Improvement Program (TQIP) registry for the year 2018. ICDPIC-R was used to derive ISS from the ICD-10 codes in the registry. The resulting scores were compared to the manually-derived ISS in TQIP.

RESULTS: The median difference between ISS derived from ICDPIC (ISS-ICDPIC) and manually-derived ISS (ISS-TQIP) was -3 [-5, 0] while the mean difference was -2.09 (-2.10, -2.07). There was substantial concordance between ISS-ICDPIC and ISS-TQIP (κ = 0.66). ISS-ICDPIC was a better predictor of mortality (AUC = 0.853 vs. 0.836) but a worse predictor of ICU admission (AUC = 0.741 vs. 0.757) and hospital stay ≥10 days (AUC = 0.701 vs. 0.743). ICDPIC has substantial concordance with TQIP for the firearm (κ = 0.69), motor vehicle trauma (κ = 0.71), and pedestrian (κ = 0.73) injury mechanisms.

CONCLUSION: When TQIP data are unavailable, ICDPIC remains a valid way to calculate ISS after transition to ICD-10 codes. ISS-ICDPIC performs well in predicting a number of outcomes of interest but is best served as a predictor of mortality. LEVEL OF EVIDENCE: Level III Prognostic and Epidemiologic.

Language: en