Mutation status concordance between 652 matched tumor and plasma 1 samples was 94.3 % ( 95 % confidence interval [ CI ] , 92.3-96 .0 ) ( comparable for mutation subtypes ) ; test sensitivity was 65.7 % ( 95 % CI , 55.8-74 .7 ) ; and test specificity was 99.8 % ( 95 % CI , 99.0-100 .0 ) .