Evaluation of specificity, sensitivity, linearity, and precision
Analytical specificity was evaluated by testing genomic DNA isolated from the positive and negative control bacterial strains. Analytical sensitivity was determined using LoB and LoD assays with samples in 22 replicates. Probit analysis was performed to measure LoD for each bacterium. The mean value of the copy number and the standard deviation (SD) were calculated. LoB was calculated as meanblank + 1.645(SDblank). LoD was calculated as meanblank + 3(SDblank)(Armbruster and Pry, 2008). The linearity was determined by a 2-fold serial dilution of the DNA template, and each dilution was measured in 8 replicates. Precision was evaluated by testing five different concentrations of genomic DNA in 8 replicates.