. Author manuscript; available in PMC: 2009 Jun 16.

Published in final edited form as: Am Heart J. 2008 Jun 6;156(1):31–36. doi: 10.1016/j.ahj.2008.03.021

Table II.

Criteria for identifying patients with clinical outcomes

Outcome	Criteria ^*	Specificity of criteria (%)
Acute MI	ICD-9 410.x (except 410.x2) as the principal or secondary diagnosis and a length of stay of >3 and <180 days	99³⁴
Unstable angina	ICD-9 411 as the principal diagnosis	96³⁵
Stroke	ICD-9 433.x1, 434 (excluding 434.x0), 435.xx, 436.xx, 437.1x or 437.9x in any diagnosis position	99³⁶
Congestive heart failure	ICD-9 428.x as the principal diagnosis	97³⁵

Based on hospital discharge codes during follow-up time.