Which method is recognized as the gold standard for urinalysis?

Gas chromatography-mass spectrometry (GC/MS) is recognized as the gold standard for urinalysis due to its high specificity and sensitivity in detecting and quantifying substances within urine samples. This method combines the separation capabilities of gas chromatography with the identification power of mass spectrometry, allowing for accurate analysis of a wide range of compounds, including various drugs and their metabolites.

GC/MS is particularly valued in toxicology because it can differentiate between closely related substances, which is crucial for providing reliable results in drug testing. This level of specificity minimizes false positives and negatives, making it a robust choice for both clinical and forensic contexts. Additionally, GC/MS can also confirm results obtained from initial screening methods, such as immunoassays, which may not have the same level of specificity.

Other methods, while useful in certain contexts, do not offer the same level of reliability as GC/MS. For instance, enzyme-linked immunosorbent assay (ELISA) is widely used for initial screenings due to its speed and convenience but can yield false positives and may not detect all substances accurately. Thin-layer chromatography (TLC) provides qualitative results but lacks the sensitivity and quantification abilities of GC/MS. Nuclear magnetic resonance (NMR) is more commonly used for structural elucid