MRO Exam A&B 2026/2027 | 400 Practice Questions, Correct Answers
& Detailed Rationales | Medical Review Officer Certification
SECTION 1 — MRO FUNDAMENTALS, ROLE & PROFESSIONAL RESPONSIBILITIES
1. What is the primary function of a Medical Review Officer (MRO)?
A. Collect every urine specimen
B. Independently review and verify laboratory drug-test results
C. Decide which employees should be tested
D. Perform all laboratory confirmation testing
Answer: B. Independently review and verify laboratory drug-test results
Rationale: The MRO provides the medical and administrative review necessary to
determine the appropriate final result.
2. Which regulation primarily governs DOT workplace drug-testing procedures?
A. 29 CFR Part 1910
B. 49 CFR Part 40
C. 45 CFR Part 46
D. 21 CFR Part 1308
Answer: B. 49 CFR Part 40
Rationale: DOT's Procedures for Transportation Workplace Drug and Alcohol
Testing Programs are contained in 49 CFR Part 40. (MROCC)
3. Which professional qualification is generally required for an MRO under DOT
rules?
A. Registered nurse only
B. Certified laboratory technician
C. Licensed physician with appropriate MRO qualifications
D. Pharmacist without medical training
Answer: C. Licensed physician with appropriate MRO qualifications
Rationale: DOT MRO functions require an appropriately qualified physician who
meets applicable certification and training requirements.
,4. During verification, the MRO should primarily determine whether:
A. The employee deserves disciplinary action
B. The laboratory result can be medically verified
C. The employer's testing policy is fair
D. The collector should be fired
Answer: B. The laboratory result can be medically verified
Rationale: The MRO's role is to review the laboratory result and relevant medical
information, not determine employer discipline.
5. Which statement best describes the MRO's relationship with the employer?
A. The MRO determines employee discipline
B. The MRO independently verifies test results
C. The MRO writes company drug policies
D. The MRO supervises all collectors
Answer: B. The MRO independently verifies test results
Rationale: Verification is a medical review function, while employment
consequences are generally determined by the employer or applicable policy.
6. What should an MRO do when an employee claims a positive result resulted
from a legitimate prescription?
A. Automatically report negative
B. Ignore the explanation
C. Evaluate the medical explanation and supporting information
D. Ask the employer to decide
Answer: C. Evaluate the medical explanation and supporting information
Rationale: DOT requires the MRO to conduct a medical interview and take
reasonable steps to evaluate legitimate medical explanations. (Department of
Transportation)
7. Which is NOT normally an MRO responsibility?
,A. Medical interview
B. Result verification
C. Medical interpretation of laboratory findings
D. Determining employee salary
Answer: D. Determining employee salary
Rationale: Salary and employment compensation are outside the MRO's medical-
review role.
8. Why is MRO independence important?
A. It eliminates laboratory testing
B. It reduces inappropriate influence on verification decisions
C. It allows the MRO to prescribe medications
D. It prevents employers from receiving results
Answer: B. It reduces inappropriate influence on verification decisions
Rationale: Independent review helps ensure that verification decisions are based
on applicable regulations, laboratory findings, and legitimate medical information.
9. What should an MRO generally do before making a verification decision on a
non-negative result?
A. Contact the employee and conduct the required review
B. Immediately notify coworkers
C. Destroy the specimen
D. Ask the employee's supervisor to interpret it
Answer: A. Contact the employee and conduct the required review
Rationale: The medical interview is a central component of the MRO verification
process. (Department of Transportation)
10. An MRO should base a DOT verification decision on:
A. Rumors about the employee
B. Unrelated non-DOT drug tests
C. The applicable laboratory result and relevant medical evidence
D. The employee's job performance alone
, Answer: C. The applicable laboratory result and relevant medical evidence
Rationale: DOT specifically restricts the MRO from considering drug tests that
were not collected or tested under Part 40. (Department of Transportation)
11. What is the main purpose of an MRO medical interview?
A. To punish the donor
B. To determine whether a legitimate medical explanation exists
C. To negotiate salary
D. To replace laboratory confirmation
Answer: B. To determine whether a legitimate medical explanation exists
Rationale: The interview allows the MRO to obtain relevant medical history and
evaluate explanations for a laboratory finding.
12. Which principle is most appropriate when discussing donor medical
information?
A. Broad disclosure
B. Minimum necessary professional disclosure
C. Public disclosure
D. Disclosure to coworkers
Answer: B. Minimum necessary professional disclosure
Rationale: Sensitive medical and drug-testing information should be handled
confidentially and disclosed only as permitted or required.
13. If an employee presents a prescription during verification, the MRO should:
A. Automatically accept it without review
B. Verify its authenticity and relevance
C. Automatically reject it
D. Send it to the employer for interpretation
Answer: B. Verify its authenticity and relevance
Rationale: DOT requires reasonable steps to verify medical records supporting a
prescription explanation. (Department of Transportation)
& Detailed Rationales | Medical Review Officer Certification
SECTION 1 — MRO FUNDAMENTALS, ROLE & PROFESSIONAL RESPONSIBILITIES
1. What is the primary function of a Medical Review Officer (MRO)?
A. Collect every urine specimen
B. Independently review and verify laboratory drug-test results
C. Decide which employees should be tested
D. Perform all laboratory confirmation testing
Answer: B. Independently review and verify laboratory drug-test results
Rationale: The MRO provides the medical and administrative review necessary to
determine the appropriate final result.
2. Which regulation primarily governs DOT workplace drug-testing procedures?
A. 29 CFR Part 1910
B. 49 CFR Part 40
C. 45 CFR Part 46
D. 21 CFR Part 1308
Answer: B. 49 CFR Part 40
Rationale: DOT's Procedures for Transportation Workplace Drug and Alcohol
Testing Programs are contained in 49 CFR Part 40. (MROCC)
3. Which professional qualification is generally required for an MRO under DOT
rules?
A. Registered nurse only
B. Certified laboratory technician
C. Licensed physician with appropriate MRO qualifications
D. Pharmacist without medical training
Answer: C. Licensed physician with appropriate MRO qualifications
Rationale: DOT MRO functions require an appropriately qualified physician who
meets applicable certification and training requirements.
,4. During verification, the MRO should primarily determine whether:
A. The employee deserves disciplinary action
B. The laboratory result can be medically verified
C. The employer's testing policy is fair
D. The collector should be fired
Answer: B. The laboratory result can be medically verified
Rationale: The MRO's role is to review the laboratory result and relevant medical
information, not determine employer discipline.
5. Which statement best describes the MRO's relationship with the employer?
A. The MRO determines employee discipline
B. The MRO independently verifies test results
C. The MRO writes company drug policies
D. The MRO supervises all collectors
Answer: B. The MRO independently verifies test results
Rationale: Verification is a medical review function, while employment
consequences are generally determined by the employer or applicable policy.
6. What should an MRO do when an employee claims a positive result resulted
from a legitimate prescription?
A. Automatically report negative
B. Ignore the explanation
C. Evaluate the medical explanation and supporting information
D. Ask the employer to decide
Answer: C. Evaluate the medical explanation and supporting information
Rationale: DOT requires the MRO to conduct a medical interview and take
reasonable steps to evaluate legitimate medical explanations. (Department of
Transportation)
7. Which is NOT normally an MRO responsibility?
,A. Medical interview
B. Result verification
C. Medical interpretation of laboratory findings
D. Determining employee salary
Answer: D. Determining employee salary
Rationale: Salary and employment compensation are outside the MRO's medical-
review role.
8. Why is MRO independence important?
A. It eliminates laboratory testing
B. It reduces inappropriate influence on verification decisions
C. It allows the MRO to prescribe medications
D. It prevents employers from receiving results
Answer: B. It reduces inappropriate influence on verification decisions
Rationale: Independent review helps ensure that verification decisions are based
on applicable regulations, laboratory findings, and legitimate medical information.
9. What should an MRO generally do before making a verification decision on a
non-negative result?
A. Contact the employee and conduct the required review
B. Immediately notify coworkers
C. Destroy the specimen
D. Ask the employee's supervisor to interpret it
Answer: A. Contact the employee and conduct the required review
Rationale: The medical interview is a central component of the MRO verification
process. (Department of Transportation)
10. An MRO should base a DOT verification decision on:
A. Rumors about the employee
B. Unrelated non-DOT drug tests
C. The applicable laboratory result and relevant medical evidence
D. The employee's job performance alone
, Answer: C. The applicable laboratory result and relevant medical evidence
Rationale: DOT specifically restricts the MRO from considering drug tests that
were not collected or tested under Part 40. (Department of Transportation)
11. What is the main purpose of an MRO medical interview?
A. To punish the donor
B. To determine whether a legitimate medical explanation exists
C. To negotiate salary
D. To replace laboratory confirmation
Answer: B. To determine whether a legitimate medical explanation exists
Rationale: The interview allows the MRO to obtain relevant medical history and
evaluate explanations for a laboratory finding.
12. Which principle is most appropriate when discussing donor medical
information?
A. Broad disclosure
B. Minimum necessary professional disclosure
C. Public disclosure
D. Disclosure to coworkers
Answer: B. Minimum necessary professional disclosure
Rationale: Sensitive medical and drug-testing information should be handled
confidentially and disclosed only as permitted or required.
13. If an employee presents a prescription during verification, the MRO should:
A. Automatically accept it without review
B. Verify its authenticity and relevance
C. Automatically reject it
D. Send it to the employer for interpretation
Answer: B. Verify its authenticity and relevance
Rationale: DOT requires reasonable steps to verify medical records supporting a
prescription explanation. (Department of Transportation)
