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Ask the President

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Q: What can our organization do if we strongly suspect that an individual was drug-exposed, but the specimen results came back negative?

A: All of USDTL’s clients can “dispute” a negative result and request a “re-test” for one or more specific drug classes that are suspected of being present. The re-test is a concept routinely used in workplace urine testing, where a subject disputes a positive result and requests a re-test, which is a re-confirmation of the specimen with a cutoff at 40 percent of the original confirmation cutoff. For non-workplace cases, clinical professionals may believe that drug exposure occurred and dispute the negative finding, which results in a re-confirmation of the disputed drug class at 40 percent of the confirmation cutoff. This re-test then becomes the result of record for the case.

To order a re-test, fax or email USDTL Client Services a re-test request on your letterhead and state the test(s) requested, the subject’s demographic information, the USDTL lab number and your contact information. You can also call Client Services with the case information. Our representative will provide you with the necessary paperwork for you to sign and return to initiate the re-test process. Once the paperwork is in order, Client Services will return a re-test result to you in one to two working days. If you have any questions after receiving the results, please contact Client Services and they will either assist you or direct you to one of our forensic toxicologists to discuss the case with you.

Visit our website to learn more about our services.

Got a question for USDTL? Ask President and Scientific Director Douglas Lewis. with your questions, please put Question for the President in the header.

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