The present teachings generally relate to methods and kits incorporating a discriminating positive control for determining whether a particular microorganism or group of microorganisms are present in a sample, for example but not limited to a food, environmental, agricultural, biopharmaceutical, pharmaceutical, or water sample. According to certain methods, at least part of a starting material, for example but not limited to, a food, environmental, agricultural, biopharmaceutical, pharmaceutical, or water sample can be combined with a culture medium and incubated under conditions suitable for microbial growth followed by extracting microorganism and added control nucleic acids for analysis. The extracted nucleic acids are amplified and the amplified nucleic acids are detected, directly or indirectly, and the fidelity of the methods and the presence or absence of the corresponding microorganism is determined because the discriminating positive control provides both confirmatory results for the methods used but eliminates false positive results.