From the Guidelines
Failure to reconfirm a split specimen drug screen result typically leads to test cancellation, as the confirmation process is crucial for verifying the accuracy of the initial positive result. When a drug test is conducted, the original specimen is often divided into two samples (A and B), and if the A sample tests positive, the donor has the right to request testing of the B sample to confirm the results 1. The process of testing split specimens is an essential quality control measure, as outlined in guidelines for good laboratory practices, which recommend testing each patient specimen in duplicate and performing serial dilutions of positive specimens to confirm positive reactions 1. If the B sample fails to confirm the presence of the drug or metabolite found in the A sample, the Medical Review Officer (MRO) must cancel the test, as the confirmation testing is essential to rule out potential laboratory errors, contamination, or other issues that might lead to a false positive.
Key Points to Consider
- The split specimen process serves as a safeguard against potentially inaccurate test results
- Confirmation testing is essential to verify the accuracy of the initial positive result
- Failure to confirm the result leads to test cancellation, which means the test cannot be used as the basis for employment actions
- The cancellation of the test result is based on the importance of ensuring the accuracy and reliability of drug test results, as emphasized in guidelines for good laboratory practices 1.
Implications for Clinical Practice
The implications of failing to reconfirm a split specimen drug screen result are significant, as it can lead to unnecessary consequences for the individual being tested. It is essential to follow proper protocols for split specimen testing to ensure the accuracy and reliability of drug test results. By doing so, healthcare providers can minimize the risk of false positives and ensure that test results are accurate and reliable.
From the Research
Failure to Reconfirm a Split Specimen Drug Screen
- There is no direct evidence in the provided studies to suggest that failure to reconfirm a split specimen drug screen result in test cancellation 2, 3, 4, 5, 6.
- The studies primarily focus on the efficacy and limitations of immunoassay drug screening tests, the importance of confirmation methods such as gas chromatography-mass spectrometry (GC-MS), and the potential for false-positive and false-negative results 2, 3, 4, 6.
- One study discusses the comparison of drug testing in urine, sweat, and hair, highlighting the advantages and limitations of each method, but does not address the specific issue of test cancellation due to failure to reconfirm a split specimen 5.
- Another study investigates the cause of false-positive amphetamine results on several drug screening platforms due to mexiletine, but does not provide information on test cancellation procedures 6.