A Medical Review Officer (MRO) is a licensed physician responsible for receiving and interpreting laboratory results from a workplace drug testing program. The MRO ensures the scientific accuracy of the test results and protects the privacy of the person tested, often called the donor. This role is particularly important in regulated industries, where the MRO serves as a neutral intermediary before results are reported to the employer.
Defining the Medical Review Officer Role
An MRO must hold a current license as a Doctor of Medicine (M.D.) or Doctor of Osteopathy (D.O.) and be in good standing with state medical boards. They are required to have specific knowledge concerning the toxicology and pharmacology of illicit drugs and controlled substances. This expertise allows them to evaluate test results in the context of a donor’s medical history.
The physician must also complete specialized training and pass a certification examination administered by an approved organization. This ensures proficiency in federal workplace drug testing guidelines and procedures, including chain of custody protocols and proper specimen collection. The MRO’s primary function is to uphold the integrity and accuracy of the drug testing process by reviewing all documentation to confirm that proper procedures were followed before a result is finalized and reported to the employer.
The Donor Verification Interview
The verification interview is the MRO’s most significant duty and is required whenever a laboratory reports a non-negative result, such as a confirmed positive, adulterated, or substituted specimen. The MRO is obligated to contact the donor privately to discuss the laboratory findings and determine if a legitimate medical explanation exists. This conversation is confidential and occurs before any result is verified and released to the employer.
The MRO must attempt to reach the donor multiple times, often within a strict 24 to 72-hour period, using the contact information provided at the time of collection. During this interview, the MRO informs the donor exactly which substance was detected and offers an opportunity to present a medical defense for its presence. A common reason for a non-negative result is the use of a legally prescribed medication, such as an opiate for pain management or certain stimulants.
If a donor claims a valid medical reason, they must provide documentation, such as a current, verifiable prescription, medical records, or a note from the prescribing physician. The MRO then contacts the pharmacy or the physician to verify the prescription’s authenticity and confirm that the dosage is consistent with the drug levels found in the specimen. If the MRO verifies the prescription and confirms legitimate use, the result reported to the employer will be converted to a verified negative.
Final Result Classification and Reporting
Following the verification interview and review of all documentation, the MRO issues a final, verified result to the employer. There are three main classifications the MRO can issue after their review: Negative, Positive, or Cancelled Test. A verified Negative result is reported if the initial non-negative finding is successfully attributed to a legitimate medical explanation, like a valid prescription.
A verified Positive result is issued when a drug or metabolite is confirmed by the lab and the donor is either unable to provide a legitimate medical explanation or declines to participate in the interview. The MRO can also classify the test as a Cancelled Test if there were documented procedural errors that compromised the integrity of the specimen or the testing process. The MRO only reports the final classification—Positive or Negative—to the employer, never disclosing the specific medical condition or the name of the prescription drug used to clear a negative result.
In certain cases, even if a result is verified as Negative due to prescription use, the MRO may still notify the employer if the medication poses a significant safety risk. This notification allows the employer to evaluate the employee’s fitness for duty, especially in safety-sensitive positions, without violating the employee’s medical privacy. The MRO ensures the final result reported is accurate and adheres to strict confidentiality standards.