title: ICD-9-CM and ICD-10-CM mapping of the AAST Emergency General Surgery disease severity grading systems: Conceptual approach, limitations, and recommendations for the future.
abstract: The American Association for the Surgery of Trauma (AAST) recently established a grading system for uniform reporting of anatomic severity of several emergency general surgery (EGS) diseases. There are five grades of severity for each disease, ranging from I (lowest severity) to V (highest severity). However, the grading process requires manual chart review. We sought to evaluate whether International Classification of Diseases, 9th and 10th Revisions, Clinical Modification (ICD-9-CM, ICD-10-CM) codes might allow estimation of AAST grades for EGS diseases. The Patient Assessment and Outcomes Committee of the AAST reviewed all available ICD-9-CM and ICD-10-CM diagnosis codes relevant to 16 EGS diseases with available AAST grades. We then matched grades for each EGS disease with one or more ICD codes. We used the Official Coding Guidelines for ICD-9-CM and ICD-10-CM and the American Hospital Association's "Coding Clinic for ICD-9-CM" for coding guidance. The ICD codes did not allow for matching all five AAST grades of severity for each of the 16 diseases. With ICD-9-CM, six diseases mapped into four categories of severity (instead of five), another six diseases into three categories of severity, and four diseases into only two categories of severity. With ICD-10-CM, five diseases mapped into four categories of severity, seven diseases into three categories, and four diseases into two categories. Two diseases mapped into discontinuous categories of grades (two in ICD-9-CM and one in ICD-10-CM). Although resolution is limited, ICD-9-CM and ICD-10-CM diagnosis codes might have some utility in roughly approximating the severity of the AAST grades in the absence of more precise information. These ICD mappings should be validated and refined before widespread use to characterize EGS disease severity. In the long-term, it may be desirable to develop alternatives to ICD-9-CM and ICD-10-CM codes for routine collection of disease severity characteristics.
authors.affiliation: From the Department of Surgery (G.H.U.), University of California, Davis, Medical Center, Sacramento, California; Department of General Surgery (P.R.M, N.T.M.), Wake Forest Baptist Health, Winston-Salem, North Carolina; Department of Surgery (G.T.T.), Scripps Memorial Hospital, San Diego, California; Department of Surgery (O.G.), Vanderbilt University Medical Center, Nashville, Tennessee; Department of Surgery (T.M.O.), University of Vermont, Colchester, Vermont; Department of Surgery (D.J.C.), Morsani College of Medicine, University of South Florida, Tampa, Florida; Department of Surgery (S.K.A.J.), University of Wisconsin, Madison, Wisconsin; Department of Surgery (K.I.), Keck School of Medicine of University of Southern California Medical Center, Los Angeles, California; Department of Surgery (M.B.A.), Virginia Commonwealth University Medical Center, Richmond, Virginia; Department of Trauma Service (C.V.R.B.), University Medical Center Brackenridge, Austin, Texas; Department of Surgery (S.E.R.), Cooper University Hospital, Camden, New Jersey; Departments of Surgery-Trauma/Critical Care and Preventive Medicine (M.L.C.), Northwestern University Feinberg School of Medicine, Chicago, Illinois; and Institute for Health Care Research and Improvement (S.S.), Baylor Health Care System, Dallas, Texas.
authors.forename: Garth H
authors.initials: GH
authors.lastname: Utter
authors.forename: Preston R
authors.initials: PR
authors.lastname: Miller
authors.forename: Nathan T
authors.initials: NT
authors.lastname: Mowery
authors.forename: Gail T
authors.initials: GT
authors.lastname: Tominaga
authors.forename: Oliver
authors.initials: O
authors.lastname: Gunter
authors.forename: Turner M
authors.initials: TM
authors.lastname: Osler
authors.forename: David J
authors.initials: DJ
authors.lastname: Ciesla
authors.forename: Suresh K
authors.initials: SK
authors.lastname: Agarwal
authors.forename: Kenji
authors.initials: K
authors.lastname: Inaba
authors.forename: Michel B
authors.initials: MB
authors.lastname: Aboutanos
authors.forename: Carlos V R
authors.initials: CV
authors.lastname: Brown
authors.forename: Steven E
authors.initials: SE
authors.lastname: Ross
authors.forename: Marie L
authors.initials: ML
authors.lastname: Crandall
authors.forename: Shahid
authors.initials: S
authors.lastname: Shafi
mesh_terms: D059019:Clinical Coding / Q000379:methods*; D004630:Emergencies; D013502:General Surgery / Q000706:statistics & numerical data*; D017408:Guidelines as Topic / Q000592:standards*; D006801:Humans; D012720:Severity of Illness Index; D012955:Societies, Medical; D014481:United States