Glossary
Medical Review Officer (MRO)
A licensed physician trained to interpret drug-test results and serve as the medical buffer between the laboratory and the employer.
Last updated:A Medical Review Officer is a licensed physician with specific training in substance abuse disorders and drug-testing regulations. The MRO reviews non-negative laboratory results, contacts the donor to identify any legitimate medical explanation (e.g., a valid prescription), and reports a verified result to the employer. Under 49 CFR Part 40, every federally regulated drug test must be reviewed by a qualified MRO.
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