Skip to main content

Table 1 Summary of sensitivity and specificity calculations at different positive droplets cut off

From: Development of a liquid biopsy based purely quantitative digital droplet PCR assay for detection of MLH1 promoter methylation in colorectal cancer patients

CUTOFF 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Sensitivity 0.96 0.96 0.93 0.93 0.93a 0.93 0.89 0.78b 0.78 0.70 0.67 0.67 0.52 0.48 0.44 0.44 0.44 0.41 0.26 0.26
Specificity 0.50 0.60 0.85 0.90 0.95a 0.95 0.95 1.00b 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
ACCURACY 0.77 0.81 0.89 0.91 0.94 0.94 0.91 0.87 0.87 0.83 0.81 0.81 0.72 0.70 0.68 0.68 0.68 0.66 0.57 0.57
PPV 0.72 0.76 0.89 0.93 0.96 0.96 0.96 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00
  1. a The optimal sensitivity and specificity were displayed at 5 positive droplets as cutoff value (93% sensitivity and 95% specificity, 95%CI: 0.78, 0.98)
  2. b As 5 positive droplets was below the reported LOD, 8 positive droplets were used as an exploratory cut-off to distinguish healthy from CRC patients (78% sensitivity and 100% specificity, 95%CI: 0.45, 0.95)