MRO: MEDICAL REVIEW OFFICER COMPLETE EXAM QUESTIONS
AND CORRECT ANSWERS| LATEST 2026/2027 UPDATE (PASS
GUARANTEED)
1. Under DOT regulations, which federal agency has primary oversight
responsibility for the workplace drug and alcohol testing program?
A. Department of Justice (DOJ)
B. Department of Transportation (DOT) ANSWER
C. Substance Abuse and Mental Health Services Administration (SAMHSA)
D. Drug Enforcement Administration (DEA)
2. Which regulation governs procedures for DOT workplace drug and alcohol
testing programs?
A. 49 CFR Part 382
B. 49 CFR Part 40 ANSWER
C. 49 CFR Part 655
D. 49 CFR Part 199
3. What is the primary role of a Medical Review Officer (MRO)?
A. To collect urine specimens from donors
B. To receive, review, and report drug test results ANSWER
C. To provide substance abuse counseling
D. To conduct workplace safety audits
4. To qualify as an MRO under DOT regulations, an individual must be a
licensed physician in:
A. The state where the employer is located
B. Any U.S. state, territory, or D.C. ANSWER
C. The state where the laboratory is located
D. The state where the donor is tested
,5. How often must an MRO complete requalification training under DOT
regulations?
A. Every year
B. Every 2 years
C. Every 3 years
D. Every 5 years ANSWER
6. Which of the following is NOT a drug included in the standard DOT 5-panel
drug test?
A. Cocaine metabolites
B. Amphetamines
C. Benzodiazepines ANSWER
D. Marijuana metabolites (THC)
7. When an MRO receives a laboratory report of a positive drug test, the MRO
must:
A. Immediately report the result to the employer
B. Contact the donor to determine if there is a legitimate medical
explanation ANSWER
C. Forward the specimen to a second laboratory for confirmation
D. Notify the Substance Abuse Professional (SAP)
8. Which of the following is a valid reason for an MRO to cancel a drug test?
A. The employee denies drug use
B. The specimen has no split specimen available
C. A fatal flaw is identified in the chain of custody ANSWER
D. The employer requests cancellation
9. What is the minimum creatinine concentration that indicates a specimen is
not consistent with normal human urine?
A. Less than 2 mg/dL ANSWER
B. Less than 5 mg/dL
C. Less than 10 mg/dL
D. Less than 20 mg/dL
10. Under 49 CFR Part 40, the MRO verification interview with a donor must be
conducted:
, A. In person only
B. By telephone or in person ANSWER
C. Via written questionnaire
D. Through the employer
SECTION 2: SPECIMEN VALIDITY TESTING (Questions 11–20)
11. A specimen is reported as substituted when creatinine is less than 2 mg/dL
AND specific gravity is:
A. Less than 1.0010 or greater than 1.0200 ANSWER
B. Less than 1.0030 or greater than 1.0300
C. Less than 1.0010 or greater than 1.0300
D. Less than 1.0020 or greater than 1.0200
12. A dilute specimen is defined as having a creatinine concentration between:
A. 2–20 mg/dL and specific gravity 1.0010–1.0030 ANSWER
B. 2–20 mg/dL and specific gravity 1.0010–1.0050
C. 5–20 mg/dL and specific gravity 1.0020–1.0030
D. 2–30 mg/dL and specific gravity 1.0010–1.0050
13. Which pH range indicates a specimen may have been adulterated?
A. Less than 3 or greater than 9
B. Less than 4 or greater than 11
C. Less than 3 or greater than 11 ANSWER
D. Less than 5 or greater than 9
14. Oxidizing adulterants such as bleach are detected by:
A. Creatinine measurement
B. Specific gravity testing
C. Chromate and nitrite testing ANSWER
D. Glutaraldehyde immunoassay
15. When a laboratory reports a specimen as adulterated, the MRO must report
the test result to the employer as:
A. Positive
B. Negative
, C. Cancelled
D. Refusal to test ANSWER
16. Nitrite concentration above what level constitutes an adulterated specimen?
A. 100 mcg/mL
B. 200 mcg/mL
C. 500 mcg/mL ANSWER
D. 1000 mcg/mL
17. When can an MRO report a dilute negative result as a negative?
A. Never; dilute specimens must always be retested
B. When the employer has no dilute specimen policy
C. Always, unless employer requires a retest ANSWER
D. Only if the donor provides a medical explanation
18. Which of the following best describes a substituted specimen?
A. A specimen that has been adulterated with a foreign substance
B. A specimen not consistent with normal human urine (not submitted
by donor) ANSWER
C. A specimen with low drug concentrations due to dilution
D. A specimen collected incorrectly by the collector
19. An MRO must cancel a test when a laboratory reports a specimen as:
A. Dilute negative
B. Invalid result with no adequate explanation ANSWER
C. Positive for a prescribed medication
D. Substituted with medical explanation
20. Glutaraldehyde is a specimen adulterant. A concentration above what level
constitutes adulteration?
A. 50 mcg/mL
B. 100 mcg/mL
C. 200 mcg/mL
D. Any detectable level ANSWER
SECTION 3: CHAIN OF CUSTODY AND DOCUMENTATION (Questions 21–30)
AND CORRECT ANSWERS| LATEST 2026/2027 UPDATE (PASS
GUARANTEED)
1. Under DOT regulations, which federal agency has primary oversight
responsibility for the workplace drug and alcohol testing program?
A. Department of Justice (DOJ)
B. Department of Transportation (DOT) ANSWER
C. Substance Abuse and Mental Health Services Administration (SAMHSA)
D. Drug Enforcement Administration (DEA)
2. Which regulation governs procedures for DOT workplace drug and alcohol
testing programs?
A. 49 CFR Part 382
B. 49 CFR Part 40 ANSWER
C. 49 CFR Part 655
D. 49 CFR Part 199
3. What is the primary role of a Medical Review Officer (MRO)?
A. To collect urine specimens from donors
B. To receive, review, and report drug test results ANSWER
C. To provide substance abuse counseling
D. To conduct workplace safety audits
4. To qualify as an MRO under DOT regulations, an individual must be a
licensed physician in:
A. The state where the employer is located
B. Any U.S. state, territory, or D.C. ANSWER
C. The state where the laboratory is located
D. The state where the donor is tested
,5. How often must an MRO complete requalification training under DOT
regulations?
A. Every year
B. Every 2 years
C. Every 3 years
D. Every 5 years ANSWER
6. Which of the following is NOT a drug included in the standard DOT 5-panel
drug test?
A. Cocaine metabolites
B. Amphetamines
C. Benzodiazepines ANSWER
D. Marijuana metabolites (THC)
7. When an MRO receives a laboratory report of a positive drug test, the MRO
must:
A. Immediately report the result to the employer
B. Contact the donor to determine if there is a legitimate medical
explanation ANSWER
C. Forward the specimen to a second laboratory for confirmation
D. Notify the Substance Abuse Professional (SAP)
8. Which of the following is a valid reason for an MRO to cancel a drug test?
A. The employee denies drug use
B. The specimen has no split specimen available
C. A fatal flaw is identified in the chain of custody ANSWER
D. The employer requests cancellation
9. What is the minimum creatinine concentration that indicates a specimen is
not consistent with normal human urine?
A. Less than 2 mg/dL ANSWER
B. Less than 5 mg/dL
C. Less than 10 mg/dL
D. Less than 20 mg/dL
10. Under 49 CFR Part 40, the MRO verification interview with a donor must be
conducted:
, A. In person only
B. By telephone or in person ANSWER
C. Via written questionnaire
D. Through the employer
SECTION 2: SPECIMEN VALIDITY TESTING (Questions 11–20)
11. A specimen is reported as substituted when creatinine is less than 2 mg/dL
AND specific gravity is:
A. Less than 1.0010 or greater than 1.0200 ANSWER
B. Less than 1.0030 or greater than 1.0300
C. Less than 1.0010 or greater than 1.0300
D. Less than 1.0020 or greater than 1.0200
12. A dilute specimen is defined as having a creatinine concentration between:
A. 2–20 mg/dL and specific gravity 1.0010–1.0030 ANSWER
B. 2–20 mg/dL and specific gravity 1.0010–1.0050
C. 5–20 mg/dL and specific gravity 1.0020–1.0030
D. 2–30 mg/dL and specific gravity 1.0010–1.0050
13. Which pH range indicates a specimen may have been adulterated?
A. Less than 3 or greater than 9
B. Less than 4 or greater than 11
C. Less than 3 or greater than 11 ANSWER
D. Less than 5 or greater than 9
14. Oxidizing adulterants such as bleach are detected by:
A. Creatinine measurement
B. Specific gravity testing
C. Chromate and nitrite testing ANSWER
D. Glutaraldehyde immunoassay
15. When a laboratory reports a specimen as adulterated, the MRO must report
the test result to the employer as:
A. Positive
B. Negative
, C. Cancelled
D. Refusal to test ANSWER
16. Nitrite concentration above what level constitutes an adulterated specimen?
A. 100 mcg/mL
B. 200 mcg/mL
C. 500 mcg/mL ANSWER
D. 1000 mcg/mL
17. When can an MRO report a dilute negative result as a negative?
A. Never; dilute specimens must always be retested
B. When the employer has no dilute specimen policy
C. Always, unless employer requires a retest ANSWER
D. Only if the donor provides a medical explanation
18. Which of the following best describes a substituted specimen?
A. A specimen that has been adulterated with a foreign substance
B. A specimen not consistent with normal human urine (not submitted
by donor) ANSWER
C. A specimen with low drug concentrations due to dilution
D. A specimen collected incorrectly by the collector
19. An MRO must cancel a test when a laboratory reports a specimen as:
A. Dilute negative
B. Invalid result with no adequate explanation ANSWER
C. Positive for a prescribed medication
D. Substituted with medical explanation
20. Glutaraldehyde is a specimen adulterant. A concentration above what level
constitutes adulteration?
A. 50 mcg/mL
B. 100 mcg/mL
C. 200 mcg/mL
D. Any detectable level ANSWER
SECTION 3: CHAIN OF CUSTODY AND DOCUMENTATION (Questions 21–30)
