What type of test is highly sensitive and specific, providing results that can be used as legal evidence?

The definitive test is characterized by its high sensitivity and specificity, which means that it can accurately identify the presence or absence of a substance with minimal false positives or negatives. This level of accuracy is crucial in clinical settings, especially when the results impact medical treatments or legal decisions. Because definitive tests provide conclusive evidence, their results are often admissible in legal contexts, making them vital in forensic science, toxicology, and situations involving criminal justice.

Definitive tests often include methods such as gas chromatography-mass spectrometry (GC-MS) or high-performance liquid chromatography (HPLC), which allow for precise measurement and identification of specific compounds down to very low concentrations. This reliability ensures that the results are not only trustworthy but can also support legal arguments and decisions based on the data provided.

In contrast, presumptive tests are typically qualitative in nature and are used as preliminary screenings to suggest the presence of a substance. While they may be useful for rapid assessments or field testing, they lack the definitive nature and legal standing that comes with the rigorous validation of definitive tests. Therefore, while both test types play important roles in clinical chemistry and forensic analysis, definitive tests stand out due to their legal validity and accuracy.