What is the methamphetamine confirmatory threshold?

What is the methamphetamine confirmatory threshold?

• A. 15 confirm
• B. 50 Ng/dl
• C. 250 confirmatory
• D. 2-3 days

Answer: (C)

The confirmatory threshold is the concentration used in the definitive test (like GC-MS or LC-MS/MS) to declare a positive result after the initial screen. For methamphetamine in urine, the standard confirmatory cutoff is 250 ng/mL. This means a specimen must contain methamphetamine at or above 250 nanograms per milliliter to be reported as confirmed positive, providing specificity by verifying the compound’s identity beyond the screening result. The other options aren’t correct because they don’t reflect a valid concentration (or they present a time frame or an odd unit, which isn’t how thresholds are defined).

The confirmatory threshold is the concentration used in the definitive test (like GC-MS or LC-MS/MS) to declare a positive result after the initial screen. For methamphetamine in urine, the standard confirmatory cutoff is 250 ng/mL. This means a specimen must contain methamphetamine at or above 250 nanograms per milliliter to be reported as confirmed positive, providing specificity by verifying the compound’s identity beyond the screening result. The other options aren’t correct because they don’t reflect a valid concentration (or they present a time frame or an odd unit, which isn’t how thresholds are defined).