A Medical Review Officer (MRO) is a person who is a licensed physician and who is responsible for receiving and reviewing laboratory results generated by an employer’s drug testing program and evaluating medical explanations for certain drug test results.As a MRO, you act as an independent and impartial “gatekeeper” and advocate for the accuracy and integrity of the drug testing process. You provide quality assurance review of the drug testing process for the specimens under your purview, determine if there is a legitimate medical explanation for laboratory confirmed positive, adulterated, substituted and invalid drug test results, ensure the timely flow of test result and other information to employers and protect the confidentiality of the drug testing information.

Source: Medical Review Officers | US Department of Transportation\\

In Summary, the MRO:

  • Is a licensed physician (M.D. or D.O.).
  • Receives and reviews (drug test) laboratory results.
  • Evaluates medical explanations for certain drug testresults.
  • Is an independent and impartial “gatekeeper.”
  • Is an advocate for accuracy and integrity.
  • Is responsible for quality assurance review.
  • Determines if there is a legitimate medical explanation
  • Ensures the timely flow of test result and otherinformation to employers.
  • Protects confidentiality