title: The Chronic Pancreatitis International Classification of Diseases, Ninth Revision, Clinical Modification Code 577.1 Is Inaccurate Compared With Criterion-Standard Clinical Diagnostic Scoring Systems.
abstract: Epidemiological studies utilizing administrative databases use the International Classification of Diseases, Ninth Revision, Clinical Modification code (577.1) to identify patients with chronic pancreatitis (CP). We hypothesized that coding of CP in these databases is inaccurate.
  
  
  
  We retrospectively reviewed the records of 1343 consecutive patients having an International Classification of Diseases, Ninth Revision, Clinical Modification code 577.1 between October 1, 2005, and November 1, 2008. We labeled patients as definite CP or non-CP, defined as fulfilling any of the 3 diagnostic criteria for definite CP: Mayo, Ammann's, and the Japanese Pancreas Society criteria.
  
  
  
  Six hundred fifty-eight subjects (49%) had definite CP. Definite CP among Mayo, Ammann's, and Japanese Pancreas Society criteria was similar (49.0, 42.1, and 43.8, respectively); 84.3% of the definite CP fulfilled all 3 criteria, 6.7% fulfilled 2, and 9.0% filled 1 criterion. Etiologies of definite CP were definite/suspected nonalcohol (57.8%) or alcohol (33.5%) and not reported (8.7%). In non-CP (n = 685), 93.7% had available imaging (5.7% had endoscopic ultrasonography ≥5 or Cambridge II-III scores), and 63.5% had symptoms suggestive of CP but did not fulfill other features for definite CP. The CP versus non-CP groups had similar mean ages but significantly more men and patients ever smoking and ever drinking alcohol.
  
  
  
  Fifty-one percent of subjects coded as CP do not fulfill the diagnostic criteria for definite CP. Relying solely on the International Classification of Diseases, Clinical Modification code for CP in administrative databases may lead to erroneous epidemiological conclusions.
authors: From the Department of Internal Medicine and Division of Gastroenterology and Hepatology, University of Michigan School of Medicine, Ann Arbor, MI.
authors: Naveen G
authors: NG
authors: Reddy
authors: Sharad
authors: S
authors: Nangia
authors: Matthew J
authors: MJ
authors: DiMagno
mesh_terms: D000428:Alcohol Drinking; D019160:Endosonography; D005260:Female; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D010179:Pancreas; D050500:Pancreatitis, Chronic