The Chronic Pancreatitis International Classification of Diseases, Ninth Revision, Clinical Modification Code 577.1...

Area of Science:

• Gastroenterology
• Epidemiology
• Health Informatics

Background:

• Administrative databases frequently use the International Classification of Diseases, Ninth Revision, Clinical Modification code 577.1 to identify patients with chronic pancreatitis (CP).
• The accuracy of this coding practice for epidemiological studies is uncertain.

Purpose of the Study:

• To evaluate the accuracy of the ICD-9 code 577.1 for identifying patients with chronic pancreatitis (CP).

Main Methods:

• Retrospective review of 1343 patient records coded with ICD-9 577.1.
• Patients were classified as definite CP or non-CP based on established diagnostic criteria (Mayo, Ammann's, Japanese Pancreas Society).

Main Results:

• 49% of patients coded with 577.1 met the criteria for definite CP.
• Among definite CP cases, most met all three diagnostic criteria.
• Non-CP patients often presented with suggestive symptoms or imaging findings but did not meet full diagnostic criteria.

Conclusions:

• A significant proportion of patients identified by the ICD-9 code 577.1 do not have definite chronic pancreatitis.
• Relying solely on this administrative code for CP may lead to inaccurate epidemiological findings.