Small Urban and Rural Center on Mobility

Transportation Glossary
Term Description

Medical Review Officer (MRO)

A licensed physician with detailed knowledge of substance abuse disorders and drug testing; an accredited physician who can review the results of drug and alcohol tests for transit employees. A MRO is mandatory for certain transit agencies under the Department of Transportation's Drug and Alcohol Regulations. The definition and qualifications for an MRO are included in 49 CFR Part 40.