Validity of International Classification of Diseases, Ninth ... : Journal of the American Society of Nephrology (original) (raw)

Clinical Nephrology

Validity of International Classification of Diseases, Ninth Revision, Clinical Modification Codes for Acute Renal Failure

Waikar, Sushrut S.*; Wald, Ron†, ‡; Chertow, Glenn M.§; Curhan, Gary C.*; Winkelmayer, Wolfgang C.*, ‖; Liangos, Orfeas‡, ¶; Sosa, Marie-Anne¶; Jaber, Bertrand L.‡, ¶

*Renal Division and Channing Laboratory, Department of Medicine; ‖Division of Pharmacoepidemiology and Pharmacoeconomics, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts; †Division of Nephrology, University of Toronto, Toronto, Ontario, Canada; ‡Division of Nephrology, Tufts-New England Medical Center, Boston, Massachusetts; §Division of Nephrology, Departments of Medicine, Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California; and ¶Division of Nephrology, Caritas St. Elizabeth’s Medical Center, Boston, Massachusetts

Address correspondence to: Dr. Sushrut S. Waikar, Channing Laboratory, 5th Floor, Brigham and Women’s Hospital, 181 Longwood Avenue, Boston, MA 02115. Phone: 617-525-2740; Fax: 617-525-2008; [email protected]

Accepted March 27, 2006

Received January 24, 2006

Abstract

Administrative and claims databases may be useful for the study of acute renal failure (ARF) and ARF that requires dialysis (ARF-D), but the validity of the corresponding diagnosis and procedure codes is unknown. The performance characteristics of International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes for ARF were assessed against serum creatinine–based definitions of ARF in 97,705 adult discharges from three Boston hospitals in 2004. For ARF-D, ICD-9-CM codes were compared with review of medical records in 150 patients with ARF-D and 150 control patients. As compared with a diagnostic standard of a 100% change in serum creatinine, ICD-9-CM codes for ARF had a sensitivity of 35.4%, specificity of 97.7%, positive predictive value of 47.9%, and negative predictive value of 96.1%. As compared with review of medical records, ICD-9-CM codes for ARF-D had positive predictive value of 94.0% and negative predictive value of 90.0%. It is concluded that administrative databases may be a powerful tool for the study of ARF, although the low sensitivity of ARF codes is an important caveat. The excellent performance characteristics of ICD-9-CM codes for ARF-D suggest that administrative data sets may be particularly well suited for research endeavors that involve patients with ARF-D.