Influence of imprecision on ROC curve analysis for cardiac markers.
BACKGROUND
There has been considerable debate regarding the impact of assay imprecision on the performance of cardiac biomarkers for diagnosis of acute coronary syndromes (ACS) and risk stratification for future adverse cardiac events.


METHODS
Using existing data from 2 published clinical trials, we used a resampling method to statistically introduce 5%, 10%, and 20% imprecision to results for B-type natriuretic peptide (BNP) and cardiac troponin I (cTnI) and examined its impact on ROC curve analysis.


RESULTS
Superimposition of artificial imprecision produced no significant difference in the area under the ROC curve observed for BNP for diagnosis of heart failure or for cTnI for 30-day risk stratification of patients with ACS.


CONCLUSIONS
Assay imprecision does not appear to be a critical determinant in the interpretation of cardiac marker results for patients with heart disease.
Nanogen, Point of Care Diagnostics Division, Toronto, Ontario, Canada.
Peter
P
Kupchak
Alan H B
AH
Wu
Farooq
F
Ghani
L Kristen
LK
Newby
E Magnus
EM
Ohman
Robert H
RH
Christenson
D000208:Acute Disease; D015415:Biomarkers / Q000097:blood; D002986:Clinical Trials as Topic; D003327:Coronary Disease / Q000175:diagnosis*; D006333:Heart Failure / Q000175:diagnosis*; D006801:Humans; D015337:Multicenter Studies as Topic; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D012372:ROC Curve; D018570:Risk Assessment; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I; D020097:Natriuretic Peptide, Brain