Stroke: who's counting what?

D M Reker; B B Hamilton; P W Duncan; S C Yeh; A Rosen

PubMed · 11392661

Stroke: who's counting what?

D M Reker·B B Hamilton·P W Duncan·S C Yeh·A Rosen

Abstract

INTRODUCTION: Patients with stroke are often selected for epidemiological reporting and research using ICD-9-CM (ICD-9) diagnostic codes. This study addresses the accuracy of these codes in identifying patients with stroke. METHODS: A sample of 279 patients with new stroke and 392 non-stroke (no evidence of new stroke) patients were identified by medical record review from 11 Veterans Affairs Medical Centers. Administrative records containing ICD-9-CM diagnoses were matched with this sample. Coding sensitivity and specificity were determined using individual ICD-9 codes and two coding algorithms. RESULTS: Significant variation was found in the accuracy of cerebrovascular ICD-9-CM codes in identifying patients diagnosed with stroke. Two coding algorithms were identified with the following performance statistics based on the sampled populations: 1) 91-percent sensitivity, 40-percent specificity; and 2) 54-percent sensitivity, 87-percent specificity. DISCUSSION/CONCLUSIONS: Variability in identifying patients with stroke using ICD-9 codes has been reported in the literature and confirmed. Two coding algorithms for maximizing sensitivity or specificity are proposed. Caution is urged when using ICD-9-coded administrative data to identify patients with stroke.

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Algorithms Humans Sensitivity and Specificity Stroke United States Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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BibTeX RIS

D M Reker, B B Hamilton, P W Duncan, S C Yeh, A Rosen. Stroke: who's counting what?. https://pubmed.ncbi.nlm.nih.gov/11392661/

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