Fig. 2.

Limit of detection. Fractions of positive reads obtained with the ValidPrime assay when analyzing samples containing from 1 to 2048 target molecules on average per sample. The measured fractions are fitted to a sigmoidal curve for the estimation of LoD (solid line). At 95% confidence LoD is 2.5 target molecules. Resampling of the data with recurrence (dashed line) allows estimating the 95% confidence interval for the LoD = 2.0 ≤ 2.5 ≤ 3.7 (intersections of the horizontal line at 0.95 and the three sigmoidal curves).