Table 2.

EGFR mutation status by ddPCR and SuperARMS.

Plasma cfDNA	Tumor tissue			Results
SuperARMS	M+	M-	Total	Sensitivity = 76.5%
M+	39	0	39	Specificity = 100%
M-	12	28	40	Positive predictive value = 100%
Total	51	28	79	Negative predictive value = 70.0% Concordance = 84.8%
ddPCR	M+	M-	Total	Sensitivity = 80.4%
M+	41	3	44	Specificity = 89.3%
M-	10	25	35	Positive predictive value = 93.2%
Total	51	28	79	Negative predictive value = 71.4% Concordance = 83.5%