What's tested on the USMLE Step 1?

The United States Medical Licensing Examination (USMLE) consists of three steps designed to assess a physician’s ability to apply a broad spectrum of knowledge, concepts, and principles, and to evaluate the physician’s basic patient-centered skills.

The Three Steps

  • Step 1 (multiple-choice exam)

    This exam is designed to test how well the examinee applies basic, integral science concepts to clinical scenarios.

  • Step 2 (two separate exams)

    • The Step 2 Clinical Knowledge (CK) is a multiple-choice exam designed to determine whether the examinee possesses the medical knowledge and understanding of clinical science considered essential for the provision of patient care under supervision.
    • The Step 2 Clinical Skills (CS) is a separate “hands-on” exam that tests the examinee’s clinical and communication skills through his/her ability to gather information from standardized patients, perform a physical examination, communicate the findings to the patient, and write a patient note.
  • Step 3 (multiple-choice exam)

    This exam assesses the examinee’s ability to apply medical knowledge and the understanding of the basic mechanisms of disease pathogenesis and treatment essential for the unsupervised practice of medicine, with emphasis on patient management in ambulatory settings.

What is USMLE Step 1?

The USMLE Step 1 is an eight-hour, computerized examination that assesses whether you understand and can apply important concepts of the sciences basic to the practice of medicine, with special emphasis on principles and mechanisms underlying health, disease, and modes oftherapy. Step 1 ensures you know the science within clinical contexts to safely and competently practice medicine under supervision.

USMLE® Step 1 at a Glance

Test Type: Computer-based
Examination Length: Seven 60-minute “blocks” administered in one eight-hour testing session; computer tutorial: 15 minutes; breaks: 45 minutes, self-scheduled
Number of Questions: Approximately 308; maximum 44 questions per block
Question Type: Single best answer multiple-choice test items
Average Time per Question: Approximately 82 seconds

The USMLE Step 1 is different and, in many ways, broader, more difficult, and more comprehensive than any exam you have ever taken in medical school. As such, it requires a different type of preparation than most medical school exams.
More time, effort, and money go into the creation of the USMLE exams than any other exam you have taken. Items on the exam are not just questions to be answered, but problems to be solved. Good USMLE questions test the students’ capacity to think about important medical knowledge and apply it in specific presented situations. The USMLE doesn’t test mere recall of facts; it assesses students’ ability to use that knowledge in clinical situations. A good knowledge base is essential, but is not sufficient. Students must know how to use the information that they know.

What is Tested on USMLE Step 1?

Step 1 consists of multiple-choice questions designed to measure basic science knowledge, including questions in anatomy, behavioral sciences, biochemistry, microbiology, pathology, pharmacology, physiology, and interdisciplinary topics, such as nutrition, genetics, and aging.
Some questions test what you know per se, but the majority of questions require you to analyze and interpret written, graphic, and tabular material. You’ll be called upon to identify gross and microscopic pathologic and normal specimens and to solve problems through application of basic science principles.
Step 1 organizes the basic science content tested according to general principles and individual organ systems. Test questions are classified in one of these major areas, depending on whether they focus on concepts and principles that are important across organ systems or within individual organ systems.

USMLE Step 1 Content Areas

  • Anatomy

  • Behavioral Sciences

  • Biochemistry

  • Biostatistics and epidemiology

  • Microbiology

  • Pathology

  • Pharmacology

  • Physiology

The Step 1 examination also includes the following interdisciplinary areas:
  • Genetics

  • Aging

  • Immunology

  • Nutrition

  • Molecular and Cell Biology

Step 1 is a broadly based, integrated examination. Test items commonly require you to perform one or more of the following tasks:
• Interpret graphic and tabular material
• Identify gross and microscopic pathologic and normal specimens
• Apply basic science knowledge to clinical problems

USMLE Step 1 Classification

Step 1 classifies test items along two dimensions, system and process.


• 15%–20% General principles
• 60%–70% Individual organ systems (hematopoietic/lymphoreticular, nervous/special senses, skin/connective tissue, musculoskeletal, respiratory, cardiovascular, gastrointestinal, renal/urinary, reproductive, endocrine, immune)
• Biostatistics, epidemiology, and population health


• 10%–15% Normal structure and function
• 55%–60% Abnormal processes
• 15%–20% Principles of therapeutics
• 10%–15% Psychosocial, cultural, occupational, and environmental consideration


How to Succeed on the USMLE

You can do well on this exam, but doing your best requires forethought and preparation. This preparation must be on several levels.

  1. You must be familiar with the types of questions you will face, as well as the overall structure of the exam itself.
  2. You must organize your study time efficiently to get the most out of it.
  3. You must know how to use the content being tested, not just recognize it. You must be able to apply it in hypothetical situations.
  4. You must physically and mentally prepare yourself for the task at hand.

In short, you must know the exam, master the material tested, and be prepared to handle yourself during this stressful time.