Ruling out coronary heart disease in primary care: external validation of a clinical prediction rule.
BACKGROUND
The Marburg Heart Score (MHS) aims to assist GPs in safely ruling out coronary heart disease (CHD) in patients presenting with chest pain, and to guide management decisions.


OBJECTIVE
To investigate the diagnostic accuracy of the MHS in an independent sample and to evaluate the generalisability to new patients.


METHODS
Cross-sectional diagnostic study with delayed-type reference standard in general practice in Hesse, Germany.


METHODS
Fifty-six German GPs recruited 844 males and females aged ≥ 35 years, presenting between July 2009 and February 2010 with chest pain. Baseline data included the items of the MHS. Data on the subsequent course of chest pain, investigations, hospitalisations, and medication were collected over 6 months and were reviewed by an independent expert panel. CHD was the reference condition. Measures of diagnostic accuracy included the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, likelihood ratios, and predictive values.


RESULTS
The AUC was 0.84 (95% confidence interval [CI] = 0.80 to 0.88). For a cut-off value of 3, the MHS showed a sensitivity of 89.1% (95% CI = 81.1% to 94.0%), a specificity of 63.5% (95% CI = 60.0% to 66.9%), a positive predictive value of 23.3% (95% CI = 19.2% to 28.0%), and a negative predictive value of 97.9% (95% CI = 96.2% to 98.9%).


CONCLUSIONS
Considering the diagnostic accuracy of the MHS, its generalisability, and ease of application, its use in clinical practice is recommended.
Department of General Practice/Family Medicine, Phillips University of Marburg, Marburg, Germany. haasenri@staff.uni-marburg.de
Jörg
J
Haasenritter
Stefan
S
Bösner
Paul
P
Vaucher
Lilli
L
Herzig
Monika
M
Heinzel-Gutenbrunner
Erika
E
Baum
Norbert
N
Donner-Banzhoff
D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002637:Chest Pain / Q000209:etiology*; D003327:Coronary Disease / Q000175:diagnosis*; D003430:Cross-Sectional Studies; D003661:Decision Support Techniques; D003937:Diagnosis, Differential; D005194:Family Practice; D005260:Female; D006801:Humans; D008297:Male; D008487:Medical History Taking; D008875:Middle Aged; D012372:ROC Curve; D012015:Reference Standards; D012680:Sensitivity and Specificity