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    **Phone:** 800-832-5660
    If you are deaf, hard of hearing, or have a speech disability, please dial 7-1-1 to access telecommunications relay services.
                
                Medical Review Officer
    

    
    
          Medical Review Officers (MRO) are licensed physicians who have been trained and certified to review the lab results and to validate whether a test is positive. MROs receive laboratory confirmed urine drug test results; determine whether there is a legitimate medical explanation for a laboratory confirmed positive, adulterated, or substituted result; and review and report a verified result to the designated employer representative (DER) in a timely and confidential manner. Regulations concerning MROs and the verification process are found in 49 CFR Part 40 Subpart G.

Find more specific information for medical review officers >>
              
      
    
          Last updated: Thursday, May 13, 2021 U.S. DEPARTMENT OF TRANSPORTATION

**Federal Motor Carrier Safety Administration**

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