What type of testing provides a positive identification of a substance through multiple steps?

Confirmatory testing is designed to provide a definitive and positive identification of a substance after it has gone through a series of carefully controlled steps. This type of testing goes beyond initial screening and typically involves methods that can unequivocally confirm the identity of a substance, such as spectrometry or chromatography.

For example, while presumptive testing may indicate the presence of a particular drug or chemical based on observable reactions or changes, confirmatory testing employs precise techniques that yield specific information about the substance, allowing investigators to conclude with confidence that a specific compound is present.

The other options describe methods that do not guarantee the same level of certainty. Presumptive testing, while useful for initial assessment, does not definitively identify a substance and may yield false positives. Colorimetric testing refers specifically to tests that rely on color changes to indicate the presence of a substance, but these results must be confirmed. Luminescence testing, which utilizes light emitted from substances, also does not provide the detailed identification necessary to reliably confirm a substance without additional methods. Therefore, confirmatory testing stands out as the most rigorous and definitive approach for substance identification.