Table 5

Paired comparison of the sensitivity and specificity of the MACS and T-MACS models for ACS in the derivation and validation studies

MACST-MACSAbsolute difference (95% CI), p value*
Derivation set
 Sensitivity99.3 (96.4–100.0)98.7 (95.3–99.8)0.7% (−0.6 to 0.7), p=1.00
 Specificity45.2 (40.9–49.4)47.6 (43.4–51.9)2.8% (1.0 to 3.8), p=0.003
Validation set
 Sensitivity100.0% (95% CI 98.1% to 100.0%)98.4% (95.4%–99.7%)1.6% (95% CI−0.7% to 1.6%), p=0.25
 Specificity20.9% (95% CI 18.6% to 22.4%)46.8% (43.9%–49.8%)25.9% (95% CI 25.3% to 25.9%), p<0.0001
  • *McNemar's test for paired proportions. N=698 in the derivation set and N=1331 in the validation set (5 patients in the derivation set and 131 in the validation set did not have an available sample for measurement of heart-type fatty acid binding protein concentration and were therefore not included in this analysis). This explains the minor differences in sensitivity and specificity compared with those reported in table 3.

  • ACS, acute coronary syndromes; T-MACS, Troponin-only Manchester Acute Coronary Syndromes.