Page 1 of 129
COMSAE PHASE 1 FORM 113 ACTUAL EXAM QUESTIONS
AND CORRECT DETAILED ANSWERS LATEST UPDATE THIS
YEAR
EXAM COVERAGE — COMSAE PHASE 1 FORM 113
The NBOME COMSAE Phase 1 examination is a comprehensive assessment designed to evaluate
a student's readiness for the COMLEX-USA Level 1. It contains 176 questions divided into four
sections of 44 questions each. All questions are single-best-answer multiple choice.
The COMSAE Phase 1 exam assesses a wide range of basic science and clinical knowledge critical
for osteopathic medical students, with a distinctive emphasis on the integration of osteopathic
principles into clinical practice.
Key content areas include:
Osteopathic Principles & Practice (OPP/OMM) — Sacral diagnosis (torsions, unilateral
flexions), pelvic somatic dysfunction (innominate rotations), rib motion (bucket handle,
pump handle), Chapman’s reflexes (anterior and posterior points), cranial rhythmic
impulse (flexion/extension phases), Counterstrain tender points, viscerosomatic reflexes,
somatic motor innervation of muscles (e.g., phrenic nerve C3–C5 for diaphragm),
Fryette’s laws (Type I and II mechanics), Still technique (indirect positioning), Muscle
Energy Technique, High-Velocity Low-Amplitude (HVLA), and fibular mechanics.
Microbiology & Immunology — Pathogenicity mechanisms (M. tuberculosis inhibition of
phagosome-lysosome fusion, Corynebacterium diphtheriae ADP-ribosylation of EF-2, C.
difficile toxin A/B), infectious mononucleosis (EBV-induced rash with amoxicillin),
diphtheria (pseudomembranous pharyngitis), SCID (adenosine deaminase deficiency),
and C. diff colitis.
Cardiovascular System — NSTEMI management (early invasive strategy with PCI), aortic
stenosis pathophysiology (concentric LV hypertrophy), cardiac amyloidosis (low voltage +
thickened LV walls), pericarditis (NSAID + colchicine), aortic regurgitation (wide pulse
pressure + De Musset's sign), HFrEF management (sacubitril/valsartan), and MI
localization on ECG (inferior wall from RCA occlusion; lateral wall from LCx).
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Neurology — CNS/PNS anatomy (CN V2 infraorbital nerve for maxillary teeth), pituitary
adenoma classification (lactotrophs for prolactinoma), medial medullary syndrome
(Dejerine), primary respiratory mechanism (cranial extension phase), methanol toxicity
(retinal toxicity from formic acid), vascular dementia (multiple lacunar infarcts), and
meningitis presentation.
Pulmonology & Renal — Asthma (reversible obstruction from bronchodilators), COPD
(Type II respiratory failure from hypoventilation), lung cancer (clubbing), pneumonia
(Klebsiella in alcoholics), TB (hemoptysis and night sweats), and hypernatremia due to
diabetes insipidus.
Gastroenterology & Hepatology — Alcohol use with confusion/ataxia/ophthalmoplegia
(Wernicke-Korsakoff syndrome), Meckel’s diverticulum, gastric ulcer pain, appendicitis,
and hepatitis presentation.
Obstetrics & Gynecology — HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low
Platelets), gestational diabetes, preterm labor risks, and ectopic pregnancy.
Hematology & Oncology — Warfarin mechanism (Vitamin K antagonist—factors II, VII,
IX, X), colon cancer screening (starting at age 45), breast cancer receptor status (ER-
positive), and lung cancer risk factors (smoking).
Biostatistics & Epidemiology — Pearson correlation values (close to 0.00 for no linear
relationship), screening guidelines, and study design interpretation.
Pharmacology — Beta-blockers (reduce mortality post-MI), ACE inhibitors (cough due to
bradykinin accumulation), penicillin allergy cross-reactivity (<1% with cephalosporins),
isotretinoin monitoring (pregnancy test), DOACs for stroke prevention, anticoagulation in
elderly, IV tPA eligibility (BP <185/110), mechanical thrombectomy for LVO, and warfarin
reversal with vitamin K.
COMSAE PHASE 1 FORM 113 — 150 RANDOMIZED SCENARIO-BASED MCQS
1. A 45-year-old male presents with chronic low back pain. Physical examination reveals an
apparent short left leg, a left posterior superior iliac spine (PSIS) that is superior compared to
the right, and a left anterior inferior iliac spine (AIIS) that is inferior compared to the right. What
is the most likely sacral diagnosis?
A. Right-on-right torsion
B. Left unilateral flexion
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C. Left-on-left torsion
D. Right unilateral flexion
Answer: C. Left-on-left torsion
RATIONALE: In sacral torsion, the side of the oblique axis is named first, and the side of the
rotation is named second. The findings (deep sulcus on the right, shallow on the left; ILA
posterior on the left) indicate rotation around a left oblique axis. A "Left-on-left" torsion means
the axis is on the left and the base is rotating anteriorly on the left.
2. A 58-year-old male with hypertension and type 2 diabetes presents with substernal chest
pressure radiating to the jaw, occurring at rest and lasting 15 minutes. ECG shows ST-segment
depression in leads V3–V6. Troponin I is elevated. Which of the following is the most
appropriate next step?
A. Aspirin and discharge with outpatient stress test
B. Oral nitroglycerin and beta-blocker at home
C. Immediate percutaneous coronary intervention (PCI)
D. Intravenous thrombolytics
Answer: C. Immediate percutaneous coronary intervention (PCI)
*RATIONALE: The patient presents with high-risk NSTEMI (elevated troponin and ongoing
symptoms). This warrants an early invasive strategy with PCI within 24 hours. Thrombolytics are
not indicated for NSTEMI.*
3. A 72-year-old female with heart failure with preserved ejection fraction (HFpEF) presents
with worsening dyspnea, JVD, and lower extremity edema. Which medication has been shown
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to reduce hospitalizations in HFpEF?
A. Digoxin
B. Spironolactone
C. Hydralazine
D. Dobutamine
Answer: B. Spironolactone
RATIONALE: The TOPCAT trial showed that spironolactone reduces hospitalizations in HFpEF
patients with elevated BNP. Digoxin does not reduce mortality or hospitalizations in HFpEF.
4. A 45-year-old male presents with palpitations. ECG shows a narrow complex tachycardia at
180 bpm with no visible P waves. Carotid sinus massage terminates the rhythm. What is the
most likely diagnosis?
A. Atrial fibrillation
B. Atrial flutter
C. AV nodal reentrant tachycardia (AVNRT)
D. Ventricular tachycardia
Answer: C. AV nodal reentrant tachycardia (AVNRT)
RATIONALE: AVNRT is a regular narrow complex tachycardia often without visible P waves. It is
frequently terminated by vagal maneuvers such as carotid sinus massage or Valsalva. Adenosine
is the first-line pharmacologic treatment.
5. A 45-year-old male with chronic low back pain is found to have a shallow right sacral sulcus
and a deep left sacral sulcus. The right inferior lateral angle (ILA) is posterior. L5 is rotated to the
COMSAE PHASE 1 FORM 113 ACTUAL EXAM QUESTIONS
AND CORRECT DETAILED ANSWERS LATEST UPDATE THIS
YEAR
EXAM COVERAGE — COMSAE PHASE 1 FORM 113
The NBOME COMSAE Phase 1 examination is a comprehensive assessment designed to evaluate
a student's readiness for the COMLEX-USA Level 1. It contains 176 questions divided into four
sections of 44 questions each. All questions are single-best-answer multiple choice.
The COMSAE Phase 1 exam assesses a wide range of basic science and clinical knowledge critical
for osteopathic medical students, with a distinctive emphasis on the integration of osteopathic
principles into clinical practice.
Key content areas include:
Osteopathic Principles & Practice (OPP/OMM) — Sacral diagnosis (torsions, unilateral
flexions), pelvic somatic dysfunction (innominate rotations), rib motion (bucket handle,
pump handle), Chapman’s reflexes (anterior and posterior points), cranial rhythmic
impulse (flexion/extension phases), Counterstrain tender points, viscerosomatic reflexes,
somatic motor innervation of muscles (e.g., phrenic nerve C3–C5 for diaphragm),
Fryette’s laws (Type I and II mechanics), Still technique (indirect positioning), Muscle
Energy Technique, High-Velocity Low-Amplitude (HVLA), and fibular mechanics.
Microbiology & Immunology — Pathogenicity mechanisms (M. tuberculosis inhibition of
phagosome-lysosome fusion, Corynebacterium diphtheriae ADP-ribosylation of EF-2, C.
difficile toxin A/B), infectious mononucleosis (EBV-induced rash with amoxicillin),
diphtheria (pseudomembranous pharyngitis), SCID (adenosine deaminase deficiency),
and C. diff colitis.
Cardiovascular System — NSTEMI management (early invasive strategy with PCI), aortic
stenosis pathophysiology (concentric LV hypertrophy), cardiac amyloidosis (low voltage +
thickened LV walls), pericarditis (NSAID + colchicine), aortic regurgitation (wide pulse
pressure + De Musset's sign), HFrEF management (sacubitril/valsartan), and MI
localization on ECG (inferior wall from RCA occlusion; lateral wall from LCx).
, Page 2 of 129
Neurology — CNS/PNS anatomy (CN V2 infraorbital nerve for maxillary teeth), pituitary
adenoma classification (lactotrophs for prolactinoma), medial medullary syndrome
(Dejerine), primary respiratory mechanism (cranial extension phase), methanol toxicity
(retinal toxicity from formic acid), vascular dementia (multiple lacunar infarcts), and
meningitis presentation.
Pulmonology & Renal — Asthma (reversible obstruction from bronchodilators), COPD
(Type II respiratory failure from hypoventilation), lung cancer (clubbing), pneumonia
(Klebsiella in alcoholics), TB (hemoptysis and night sweats), and hypernatremia due to
diabetes insipidus.
Gastroenterology & Hepatology — Alcohol use with confusion/ataxia/ophthalmoplegia
(Wernicke-Korsakoff syndrome), Meckel’s diverticulum, gastric ulcer pain, appendicitis,
and hepatitis presentation.
Obstetrics & Gynecology — HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low
Platelets), gestational diabetes, preterm labor risks, and ectopic pregnancy.
Hematology & Oncology — Warfarin mechanism (Vitamin K antagonist—factors II, VII,
IX, X), colon cancer screening (starting at age 45), breast cancer receptor status (ER-
positive), and lung cancer risk factors (smoking).
Biostatistics & Epidemiology — Pearson correlation values (close to 0.00 for no linear
relationship), screening guidelines, and study design interpretation.
Pharmacology — Beta-blockers (reduce mortality post-MI), ACE inhibitors (cough due to
bradykinin accumulation), penicillin allergy cross-reactivity (<1% with cephalosporins),
isotretinoin monitoring (pregnancy test), DOACs for stroke prevention, anticoagulation in
elderly, IV tPA eligibility (BP <185/110), mechanical thrombectomy for LVO, and warfarin
reversal with vitamin K.
COMSAE PHASE 1 FORM 113 — 150 RANDOMIZED SCENARIO-BASED MCQS
1. A 45-year-old male presents with chronic low back pain. Physical examination reveals an
apparent short left leg, a left posterior superior iliac spine (PSIS) that is superior compared to
the right, and a left anterior inferior iliac spine (AIIS) that is inferior compared to the right. What
is the most likely sacral diagnosis?
A. Right-on-right torsion
B. Left unilateral flexion
, Page 3 of 129
C. Left-on-left torsion
D. Right unilateral flexion
Answer: C. Left-on-left torsion
RATIONALE: In sacral torsion, the side of the oblique axis is named first, and the side of the
rotation is named second. The findings (deep sulcus on the right, shallow on the left; ILA
posterior on the left) indicate rotation around a left oblique axis. A "Left-on-left" torsion means
the axis is on the left and the base is rotating anteriorly on the left.
2. A 58-year-old male with hypertension and type 2 diabetes presents with substernal chest
pressure radiating to the jaw, occurring at rest and lasting 15 minutes. ECG shows ST-segment
depression in leads V3–V6. Troponin I is elevated. Which of the following is the most
appropriate next step?
A. Aspirin and discharge with outpatient stress test
B. Oral nitroglycerin and beta-blocker at home
C. Immediate percutaneous coronary intervention (PCI)
D. Intravenous thrombolytics
Answer: C. Immediate percutaneous coronary intervention (PCI)
*RATIONALE: The patient presents with high-risk NSTEMI (elevated troponin and ongoing
symptoms). This warrants an early invasive strategy with PCI within 24 hours. Thrombolytics are
not indicated for NSTEMI.*
3. A 72-year-old female with heart failure with preserved ejection fraction (HFpEF) presents
with worsening dyspnea, JVD, and lower extremity edema. Which medication has been shown
, Page 4 of 129
to reduce hospitalizations in HFpEF?
A. Digoxin
B. Spironolactone
C. Hydralazine
D. Dobutamine
Answer: B. Spironolactone
RATIONALE: The TOPCAT trial showed that spironolactone reduces hospitalizations in HFpEF
patients with elevated BNP. Digoxin does not reduce mortality or hospitalizations in HFpEF.
4. A 45-year-old male presents with palpitations. ECG shows a narrow complex tachycardia at
180 bpm with no visible P waves. Carotid sinus massage terminates the rhythm. What is the
most likely diagnosis?
A. Atrial fibrillation
B. Atrial flutter
C. AV nodal reentrant tachycardia (AVNRT)
D. Ventricular tachycardia
Answer: C. AV nodal reentrant tachycardia (AVNRT)
RATIONALE: AVNRT is a regular narrow complex tachycardia often without visible P waves. It is
frequently terminated by vagal maneuvers such as carotid sinus massage or Valsalva. Adenosine
is the first-line pharmacologic treatment.
5. A 45-year-old male with chronic low back pain is found to have a shallow right sacral sulcus
and a deep left sacral sulcus. The right inferior lateral angle (ILA) is posterior. L5 is rotated to the