Lab Based Drug Test
Lab-based drug testing is when samples are sent to a certified laboratory to undergo an initial screening test and more stringent confirmatory testing for drugs (e.g., cocaine, marijuana, and amphetamines) and specimen validity (e.g., to determine if the sample has been tampered with). These screening tests tend to be fairly specific and highly sensitive for the drugs being analyzed. If a non-negative sample is detected, labs utilize technologies like gas chromatography/mass spectrometry (GC/MS) to confirm the presence or absence of specific drugs, thereby preventing false positives.
Additionally, lab-based drug testing goes through a chain of custody, which is the recordkeeping process of who handles a drug testing sample and why from the time the sample is collected to the time the sample is discarded. Chain of Custody documentation includes both the original sample and any portion of the sample that might be removed from the original container. The documentation provides a paper trail showing the collection, transfer, testing, and disposal of the sample, further verifying its integrity and holds up to any legal scrutiny.