NBOME

COMLEX Level 1

Comprehensive Osteopathic Medical Licensing Examination of the United States, Level 1

The first of three licensure exams every osteopathic (DO) medical student must pass, testing foundational biomedical sciences and osteopathic principles. Pass/fail since 2022 and required to progress toward DO licensure.

About 8 hours of testing plus breaks (one day)Required to practice

What's on the exam

COMLEX-USA Master Blueprint, Level 1 (Dimension 2: Clinical Presentations)

Community Health and Patient Presentations Related to Wellness

~6%

Preventive medicine · Epidemiology and biostatistics · Health promotion · Population health · Medical ethics

Human Development, Reproduction, and Sexuality

~7%

Embryology · Reproductive physiology · Pregnancy and fetal development · Genetics and inheritance · Lifespan development

Endocrine System and Metabolism

~8%

Hormone signaling · Glucose regulation and diabetes · Thyroid and adrenal disorders · Metabolic pathways · Nutrition and vitamins

Nervous System and Mental Health

~13%

Neuroanatomy · Neurophysiology · Neuropharmacology · Behavioral science · Psychiatric pathophysiology

Musculoskeletal System

~14%

Anatomy of the spine and extremities · Osteopathic structural diagnosis · OMT principles and techniques · Somatic dysfunction · Rheumatologic pathology

Genitourinary/Renal System and Breasts

~7%

Renal physiology · Acid–base balance · Nephron pathology · Genitourinary anatomy · Breast pathology

Gastrointestinal System and Nutritional Health

~11%

GI anatomy and histology · Digestive physiology · Hepatobiliary function · GI microbiology · Nutritional deficiencies

Circulatory and Hematologic Systems

~13%

Cardiac physiology · Cardiovascular pathology · Hemostasis and coagulation · Hematologic malignancies · Cardiovascular pharmacology

Respiratory System

~12%

Pulmonary physiology · Gas exchange and transport · Respiratory pathology · Pulmonary infections · Acid–base compensation

Integumentary System

~9%

Skin anatomy and histology · Dermatologic pathology · Skin infections · Immunologic skin disorders · Wound healing

Frequently asked questions

How much does the COMLEX Level 1 cost?

Fees vary. Approximately $760; confirm the current NBOME fee schedule.

How long is the COMLEX Level 1 and how many questions does it have?

352 items — About 8 hours of testing plus breaks (one day).

What do you need to pass the COMLEX Level 1?

Pass/fail against the NBOME standard (numeric scores discontinued in 2022).

Can you retake the COMLEX Level 1?

Retake permitted only after a failing attempt; attempt limits and waiting periods set by NBOME.

What is the best way to study for the COMLEX Level 1?

Study the official blueprint, not random material: the exam is weighted by domain (Community Health and Patient Presentations Related to Wellness ~6%, Human Development, Reproduction, and Sexuality ~7%, Endocrine System and Metabolism ~8%, Nervous System and Mental Health ~13%, Musculoskeletal System ~14%, Genitourinary/Renal System and Breasts ~7%, Gastrointestinal System and Nutritional Health ~11%, Circulatory and Hematologic Systems ~13%, Respiratory System ~12%, Integumentary System ~9%). Spaced-repetition flashcards built domain-by-domain against that blueprint are the most time-efficient way to cover everything the exam tests.

Program in development

We're building a blueprint-complete program for this exam. Meanwhile, explore live programs across 7 exam.

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