MRO Actual Exam 2026–2027 | 100 Questions & Correct Answers
MEDICAL REVIEW OFFICER (MRO)
ACTUAL EXAM 2026–2027
100 Questions and Correct Answers | Graded A+ | 100% Verified
Key Domains: Federal Drug Testing Guidelines (HHS/DOT), 49 CFR Part 40, MRO Responsibilities,
Chain of Custody Procedures, Adulteration and Substitution, Validity Testing, Ethical/Legal Standards
INSTRUCTIONS
Each question is followed by four options (A–D). The correct answer is highlighted in bold
cyan along with a concise rationale explaining the reasoning. Read each question carefully and
select the best answer.
Domain 1: Federal Drug Testing Guidelines (HHS/DOT)
1. Under the Mandatory Guidelines for Federal Workplace Drug Testing established by HHS, which of the
following is the primary specimen type required for drug testing?
A. Oral fluid B. Hair
C. Urine D. Blood
Answer: C
Rationale: Urine is the primary specimen type mandated by the HHS Mandatory Guidelines. Oral fluid and hair are
authorized as alternate specimens under DOT regulations but are not the primary required specimen for federal drug
testing programs.
2. Which federal agency is responsible for establishing the scientific and technical procedures for drug testing
under the Mandatory Guidelines?
A. Department of Transportation (DOT)
B. Substance Abuse and Mental Health Services Administration (SAMHSA)
C. Occupational Safety and Health Administration (OSHA)
D. Drug Enforcement Administration (DEA)
Answer: B
Rationale: SAMHSA, within HHS, is responsible for establishing the Mandatory Guidelines including the scientific and
technical procedures for federal workplace drug testing, including specimen collection, testing methods, and cutoff levels.
3. The HHS Mandatory Guidelines establish initial and confirmatory cutoff concentrations for which of the
following drug classes?
A. Amphetamines, Cocaine, Opiates, Phencyclidine, and Marijuana
B. Amphetamines, Barbiturates, Benzodiazepines, and Cocaine
C. Marijuana, Alcohol, Nicotine, and Cocaine
D. Opiates, Steroids, Cocaine, and LSD
Answer: A
1
, MRO Actual Exam 2026–2027 | 100 Questions & Correct Answers
Rationale: The five drug classes (sometimes called the SAMHSA-5) under the Mandatory Guidelines are amphetamines,
cocaine (benzoylecgonine), opiates, phencyclidine (PCP), and marijuana (THC metabolite). These form the standard
federal panel.
4. What is the initial screening cutoff concentration for marijuana metabolite (THCA) in urine under current HHS
Mandatory Guidelines?
A. 50 ng/mL B. 100 ng/mL
C. 25 ng/mL D. 15 ng/mL
Answer: A
Rationale: The initial screening cutoff for marijuana metabolite (THCA) under current HHS Mandatory Guidelines is 50
ng/mL. The confirmatory cutoff using GC/MS is 15 ng/mL. The screening cutoff remains 50 ng/mL.
5. Which specimen type was added by HHS as an authorized alternative for federal drug testing under revisions to
the Mandatory Guidelines?
A. Hair specimen B. Oral fluid
C. Sweat patch D. Nail clippings
Answer: B
Rationale: HHS added oral fluid as an authorized alternative specimen for federal workplace drug testing in the revised
Mandatory Guidelines. Oral fluid testing has specific collection, handling, and testing requirements distinct from urine
testing.
6. DOT drug testing rules apply to which of the following transportation industry employees?
A. All employees in any industry nationwide
B. Safety-sensitive employees in aviation, trucking, rail, maritime, pipeline, and mass transit
C. Only commercial airline pilots
D. Only truck drivers with vehicles over 10,000 lbs
Answer: B
Rationale: DOT regulations under 49 CFR Part 40 apply to safety-sensitive employees across six transportation modes:
aviation (FAA), trucking/bus (FMCSA), rail (FRA), maritime (USCG), pipeline (PHMSA), and mass transit (FTA).
7. Under the HHS Mandatory Guidelines, which analytical method must be used for confirmatory drug testing?
A. Enzyme multiplied immunoassay technique (EMIT)
B. Gas chromatography/mass spectrometry (GC/MS)
C. Radioimmunoassay (RIA)
D. High-performance liquid chromatography (HPLC)
Answer: B
Rationale: GC/MS (or an equivalent confirmatory method such as LC/MS/MS) is the mandatory confirmatory method
under HHS guidelines. Initial immunoassay screening results must be confirmed using GC/MS before a result can be
reported as positive.
8. What is the role of the Department of Health and Human Services (HHS) in federal drug testing?
A. Conducting drug tests directly for federal employees
B. Establishing Mandatory Guidelines for specimen collection, testing, and reporting
C. Certifying Medical Review Officers directly
D. Employing collectors for DOT-regulated employers
Answer: B
Rationale: HHS establishes the Mandatory Guidelines that govern specimen collection, laboratory testing, reporting, and
MRO review. HHS does not directly conduct tests, certify MROs (that is done by MROCC or AAMRO), or employ
collectors.
2
, MRO Actual Exam 2026–2027 | 100 Questions & Correct Answers
9. Which of the following accurately describes the relationship between HHS Mandatory Guidelines and DOT
drug testing regulations?
A. DOT regulations are independent of HHS guidelines
B. DOT incorporates HHS Mandatory Guidelines by reference in 49 CFR Part 40
C. DOT has its own separate testing panel different from HHS
D. HHS guidelines only apply to DOT, not other federal agencies
Answer: B
Rationale: DOT incorporates the HHS Mandatory Guidelines by reference in 49 CFR Part 40. The DOT adds additional
requirements for transportation-specific scenarios (post-accident, reasonable suspicion, etc.) but relies on HHS for the
scientific testing standards.
10. Under federal guidelines, which of the following substances is NOT part of the standard five-panel drug test?
A. Cocaine metabolite B. Barbiturates
C. Opiates D. Phencyclidine (PCP)
Answer: B
Rationale: Barbiturates are not included in the standard five-panel drug test. The mandatory panel includes
amphetamines, cocaine, opiates, PCP, and marijuana. Expanded panels may include additional substances but are not
mandated under the standard guidelines.
11. When HHS revises the Mandatory Guidelines, which of the following must occur before laboratories must
implement the changes?
A. Immediate implementation upon publication
B. A period for public notice and comment before compliance deadlines
C. Laboratories must update procedures only when DOT issues matching rules
D. No changes are permitted to the Mandatory Guidelines once published
Answer: B
Rationale: HHS must provide notice and allow a period for public comment before revising the Mandatory Guidelines,
and typically provides a compliance timeline. Changes do not take effect immediately upon publication.
12. The initial screening cutoff for cocaine metabolite (benzoylecgonine) under HHS guidelines is:
A. 150 ng/mL B. 100 ng/mL
C. 300 ng/mL D. 50 ng/mL
Answer: A
Rationale: The initial screening cutoff for benzoylecgonine (cocaine metabolite) is 150 ng/mL under HHS Mandatory
Guidelines. The confirmatory GC/MS cutoff is 100 ng/mL.
13. Which agency within DOT has authority to implement drug testing regulations for the trucking and bus
industry?
A. Federal Aviation Administration (FAA)
B. Federal Motor Carrier Safety Administration (FMCSA)
C. Federal Railroad Administration (FRA)
D. Pipeline and Hazardous Materials Safety Administration (PHMSA)
Answer: B
Rationale: The FMCSA regulates drug and alcohol testing for commercial motor vehicle drivers, including truck and bus
operators, under the authority granted by 49 CFR Part 40 and its own agency-specific regulations in 49 CFR Part 382.
14. What does the term HHS-certified laboratory mean in the context of federal drug testing?
A. A laboratory that follows general clinical testing standards
3
MEDICAL REVIEW OFFICER (MRO)
ACTUAL EXAM 2026–2027
100 Questions and Correct Answers | Graded A+ | 100% Verified
Key Domains: Federal Drug Testing Guidelines (HHS/DOT), 49 CFR Part 40, MRO Responsibilities,
Chain of Custody Procedures, Adulteration and Substitution, Validity Testing, Ethical/Legal Standards
INSTRUCTIONS
Each question is followed by four options (A–D). The correct answer is highlighted in bold
cyan along with a concise rationale explaining the reasoning. Read each question carefully and
select the best answer.
Domain 1: Federal Drug Testing Guidelines (HHS/DOT)
1. Under the Mandatory Guidelines for Federal Workplace Drug Testing established by HHS, which of the
following is the primary specimen type required for drug testing?
A. Oral fluid B. Hair
C. Urine D. Blood
Answer: C
Rationale: Urine is the primary specimen type mandated by the HHS Mandatory Guidelines. Oral fluid and hair are
authorized as alternate specimens under DOT regulations but are not the primary required specimen for federal drug
testing programs.
2. Which federal agency is responsible for establishing the scientific and technical procedures for drug testing
under the Mandatory Guidelines?
A. Department of Transportation (DOT)
B. Substance Abuse and Mental Health Services Administration (SAMHSA)
C. Occupational Safety and Health Administration (OSHA)
D. Drug Enforcement Administration (DEA)
Answer: B
Rationale: SAMHSA, within HHS, is responsible for establishing the Mandatory Guidelines including the scientific and
technical procedures for federal workplace drug testing, including specimen collection, testing methods, and cutoff levels.
3. The HHS Mandatory Guidelines establish initial and confirmatory cutoff concentrations for which of the
following drug classes?
A. Amphetamines, Cocaine, Opiates, Phencyclidine, and Marijuana
B. Amphetamines, Barbiturates, Benzodiazepines, and Cocaine
C. Marijuana, Alcohol, Nicotine, and Cocaine
D. Opiates, Steroids, Cocaine, and LSD
Answer: A
1
, MRO Actual Exam 2026–2027 | 100 Questions & Correct Answers
Rationale: The five drug classes (sometimes called the SAMHSA-5) under the Mandatory Guidelines are amphetamines,
cocaine (benzoylecgonine), opiates, phencyclidine (PCP), and marijuana (THC metabolite). These form the standard
federal panel.
4. What is the initial screening cutoff concentration for marijuana metabolite (THCA) in urine under current HHS
Mandatory Guidelines?
A. 50 ng/mL B. 100 ng/mL
C. 25 ng/mL D. 15 ng/mL
Answer: A
Rationale: The initial screening cutoff for marijuana metabolite (THCA) under current HHS Mandatory Guidelines is 50
ng/mL. The confirmatory cutoff using GC/MS is 15 ng/mL. The screening cutoff remains 50 ng/mL.
5. Which specimen type was added by HHS as an authorized alternative for federal drug testing under revisions to
the Mandatory Guidelines?
A. Hair specimen B. Oral fluid
C. Sweat patch D. Nail clippings
Answer: B
Rationale: HHS added oral fluid as an authorized alternative specimen for federal workplace drug testing in the revised
Mandatory Guidelines. Oral fluid testing has specific collection, handling, and testing requirements distinct from urine
testing.
6. DOT drug testing rules apply to which of the following transportation industry employees?
A. All employees in any industry nationwide
B. Safety-sensitive employees in aviation, trucking, rail, maritime, pipeline, and mass transit
C. Only commercial airline pilots
D. Only truck drivers with vehicles over 10,000 lbs
Answer: B
Rationale: DOT regulations under 49 CFR Part 40 apply to safety-sensitive employees across six transportation modes:
aviation (FAA), trucking/bus (FMCSA), rail (FRA), maritime (USCG), pipeline (PHMSA), and mass transit (FTA).
7. Under the HHS Mandatory Guidelines, which analytical method must be used for confirmatory drug testing?
A. Enzyme multiplied immunoassay technique (EMIT)
B. Gas chromatography/mass spectrometry (GC/MS)
C. Radioimmunoassay (RIA)
D. High-performance liquid chromatography (HPLC)
Answer: B
Rationale: GC/MS (or an equivalent confirmatory method such as LC/MS/MS) is the mandatory confirmatory method
under HHS guidelines. Initial immunoassay screening results must be confirmed using GC/MS before a result can be
reported as positive.
8. What is the role of the Department of Health and Human Services (HHS) in federal drug testing?
A. Conducting drug tests directly for federal employees
B. Establishing Mandatory Guidelines for specimen collection, testing, and reporting
C. Certifying Medical Review Officers directly
D. Employing collectors for DOT-regulated employers
Answer: B
Rationale: HHS establishes the Mandatory Guidelines that govern specimen collection, laboratory testing, reporting, and
MRO review. HHS does not directly conduct tests, certify MROs (that is done by MROCC or AAMRO), or employ
collectors.
2
, MRO Actual Exam 2026–2027 | 100 Questions & Correct Answers
9. Which of the following accurately describes the relationship between HHS Mandatory Guidelines and DOT
drug testing regulations?
A. DOT regulations are independent of HHS guidelines
B. DOT incorporates HHS Mandatory Guidelines by reference in 49 CFR Part 40
C. DOT has its own separate testing panel different from HHS
D. HHS guidelines only apply to DOT, not other federal agencies
Answer: B
Rationale: DOT incorporates the HHS Mandatory Guidelines by reference in 49 CFR Part 40. The DOT adds additional
requirements for transportation-specific scenarios (post-accident, reasonable suspicion, etc.) but relies on HHS for the
scientific testing standards.
10. Under federal guidelines, which of the following substances is NOT part of the standard five-panel drug test?
A. Cocaine metabolite B. Barbiturates
C. Opiates D. Phencyclidine (PCP)
Answer: B
Rationale: Barbiturates are not included in the standard five-panel drug test. The mandatory panel includes
amphetamines, cocaine, opiates, PCP, and marijuana. Expanded panels may include additional substances but are not
mandated under the standard guidelines.
11. When HHS revises the Mandatory Guidelines, which of the following must occur before laboratories must
implement the changes?
A. Immediate implementation upon publication
B. A period for public notice and comment before compliance deadlines
C. Laboratories must update procedures only when DOT issues matching rules
D. No changes are permitted to the Mandatory Guidelines once published
Answer: B
Rationale: HHS must provide notice and allow a period for public comment before revising the Mandatory Guidelines,
and typically provides a compliance timeline. Changes do not take effect immediately upon publication.
12. The initial screening cutoff for cocaine metabolite (benzoylecgonine) under HHS guidelines is:
A. 150 ng/mL B. 100 ng/mL
C. 300 ng/mL D. 50 ng/mL
Answer: A
Rationale: The initial screening cutoff for benzoylecgonine (cocaine metabolite) is 150 ng/mL under HHS Mandatory
Guidelines. The confirmatory GC/MS cutoff is 100 ng/mL.
13. Which agency within DOT has authority to implement drug testing regulations for the trucking and bus
industry?
A. Federal Aviation Administration (FAA)
B. Federal Motor Carrier Safety Administration (FMCSA)
C. Federal Railroad Administration (FRA)
D. Pipeline and Hazardous Materials Safety Administration (PHMSA)
Answer: B
Rationale: The FMCSA regulates drug and alcohol testing for commercial motor vehicle drivers, including truck and bus
operators, under the authority granted by 49 CFR Part 40 and its own agency-specific regulations in 49 CFR Part 382.
14. What does the term HHS-certified laboratory mean in the context of federal drug testing?
A. A laboratory that follows general clinical testing standards
3
