Is my Prometric test center open?

Click here to check on the status of your test center.

Step 2 CK Announcements

Bulletin of Information

The USMLE Bulletin of Information is a compilation of all the facts and details about the USMLE. Before you apply for any of the three steps of the USMLE, you must become familiar with the bulletin.

Step 2 CK assesses an examinee’s ability to apply medical knowledge, skills, and understanding of clinical science essential for the provision of patient care under supervision and includes emphasis on health promotion and disease prevention. Step 2 CK ensures that due attention is devoted to principles of clinical sciences and basic patient-centered skills that provide the foundation for the safe and competent practice of medicine under supervision.

Step 2 CK is a one-day examination. It is divided into eight 60-minute blocks and administered in one 9-hour testing session. The number of questions per block on a given examination will vary but will not exceed 40. The total number of items on the overall examination will not exceed 318.

The examination also includes a minimum allotment of 45 minutes of break time and a 15-minute optional tutorial. The amount of time available for breaks may be increased by finishing a block of test items or the optional tutorial before the allotted time expires.

Practice materials, which include Sample Test Items (PDF) and simulated web-based Tutorial and Practice Test Items, tutorials, as well as other informational materials are available at the USMLE website. Examinees must also read the USMLE Bulletin of Information.


  • The term item is used to describe a test question in any format.
  • You must run the web-based Tutorial and Practice Test Items to become familiar with the test software prior to your test date.
  • The tutorial provided at the beginning of the Step 2 CK Examination has fewer screens and less detailed information than the Step 2 CK web-based Tutorial and Practice Test Items on the USMLE website.
  • The web-based Tutorial and Practice Test Items on USMLE website include single multiple-choice questions, a sequential set of multiple-choice questions, a scientific abstract (a summary of an experiment or clinical investigation, accompanied by two or more questions), and items with audio or video findings.

Please visit the USMLE website often to view announcements, regarding changes in test delivery software, and to access updated practice materials. You must obtain the most recent information before taking any USMLE examination.

Beginning in November 2020, Step 2 CK examinations will include an increased number of questions that assess systems-based practice, patient safety, legal/ethical issues, and professionalism. The tables below provide information on the content weighting for Step 2 CK examinations administered before and after November 2020.

All USMLE examinations are constructed from an integrated content outline. Content is organized according to general principles and individual organ systems. Test questions are classified into one of 18 major categories, depending on whether they focus on concepts and principles that are applicable across organ systems or within individual organ systems.

Content weighting for these topics is provided in Table 1 below. Sections focusing on individual organ systems are subdivided into normal and abnormal processes, including principles of therapy. In most instances, knowledge of normal processes is evaluated in the context of a disease process or specific pathology.

While not all topics listed in the content outline are included in every USMLE examination, overall content coverage is comparable among the various examinations that will be administered to different examinees for each Step.

Table 1: Step 2 CK System Specifications*

System Range, %
General Principles of Foundational Science** 2–4
Immune System 3–5
Blood & Lymphoreticular System 4–6
Behavioral Health 6–8
Nervous System & Special Senses 6–8
Musculoskeletal System/Skin & Subcutaneous Tissue 6–10
Cardiovascular System 8–10
Respiratory System 7–9
Gastrointestinal System 7–9
Renal & Urinary System & Male Reproductive 4–6
Pregnancy, Childbirth & the Puerperium 4–6
Female Reproductive System & Breast 4–6
Endocrine System 4–6
Multisystem Processes & Disorders 4–6
Biostatistics & Epidemiology/Population Health/Interpretation of Medical Literature 3–5  
Social Sciences: Legal/Ethical Issues & Professionalism/Systems-based Practice & Patient Safety 10–15  

* Percentages are subject to change at any time.
** The General Principles category for the Step 2 CK examination includes test items concerning those normal and abnormal processes that are not limited to specific organ systems. Categories for individual organ systems include test items concerning those normal and abnormal processes that are system-specific.

Physician Tasks/Competencies

An additional organizing construct for Step 2 CK design is physician tasks and competencies. Each test item is constructed to focus on assessing one of the competencies listed in Table 2. Click here for detailed information about the physician tasks and competencies outline

Table 2: Step 2 CK Physician Task/Competencies Specifications*

Competency Range, %
Medical Knowledge: Applying Foundational Science Concepts 0**
Patient Care: History and Physical Exam 0***
Patient Care: Laboratory/Diagnostic Studies 13–17
Patient Care: Diagnosis 16–20
Patient Care: Prognosis/Outcome 5–9
Patient Care: Health Maintenance/Disease Prevention 8–12
Patient Care: Pharmacotherapy 8–12
Patient Care: Clinical Interventions 6–10
Patient Care: Mixed Management 12–16
Practice-based Learning & Improvement 3–5
Professionalism 5–7
Systems-based Practice & Patient Safety 5–7

* Percentages are subject to change at any time.
** Test items that assess patient care competencies may also assess knowledge of underlying foundational science concepts.
*** Test items that assess history and physical exam competencies will be covered in Step 1 examinations.

Each Step 2 CK examination covers content related to the traditionally defined disciplines listed in Table 3.

Table 3: Step 2 CK Discipline Specifications*

Range, %
Obstetrics & Gynecology

* Percentages are subject to change at any time.

Step 2 CK consists of multiple-choice questions (MCQs) prepared by examination committees composed of prominent faculty members, teachers, investigators, and clinicians who make up the USMLE Test Material Development Committees. All committee members have recognized expertise in their respective fields. They are selected to provide broad representation from the academic, practice, and licensing communities across the United States and Canada.

Test questions focus on the principles of clinical science that are deemed important for the practice of medicine under supervision in postgraduate training.

The content description is not intended as a curriculum development or study guide, but rather models the range of challenges that will be met in the actual practice of medicine. It provides a flexible structure for test construction that can readily accommodate new topics, emerging content domains, and shifts in emphasis. The categorizations and content coverage are subject to change.

The best preparation for the examination is broad-based learning that establishes a strong general understanding of concepts and principles in the basic and clinical sciences.


  • Read each question carefully. It is important to understand what is being asked.
  • Try to generate an answer and then look for it in the response option list.
  • Alternatively, read each option carefully, eliminating those that are clearly incorrect.
  • Of the remaining options, select the one that is most correct.
  • If unsure about an answer, it is better to guess since unanswered questions are automatically counted as wrong answers.

Single-Item Questions

This is the traditional, most frequently used multiple-choice format. It consists of a vignette and question followed by three to twenty-six options that are in alphabetical or logical order. The response options in this format are lettered (eg, A, B, C, D, E). You are required to select the one best answer to the question. Other options may be partially correct, but there is only ONE BEST answer.

Example Item

A 32-year-old woman with type 1 diabetes mellitus has had progressive renal failure over the past 2 years. She is not yet on dialysis. Examination shows no abnormalities. Her hemoglobin concentration is 9 g/dL, hematocrit is 28%, and mean corpuscular volume is 94 m3. A blood smear shows normochromic, normocytic cells. Which of the following is the most likely cause?

  1. Acute blood loss
  2. Chronic lymphocytic leukemia
  3. Erythrocyte enzyme deficiency
  4. Erythropoietin deficiency
  5. Immunohemolysis
  6. Microangiopathic hemolysis
  7. Polycythemia vera
  8. Sickle cell disease
  9. Sideroblastic anemia
  10. β-Thalassemia trait

(Answer: D)

Sequential Item Sets

A single patient-centered vignette may be associated with two or three consecutive questions about the information presented. Each question is associated with the initial patient vignette but is testing a different point. You are required to select the ONE BEST answer to each question. Questions are designed to be answered in sequential order. You must click “Proceed to Next Item” to view the next item in the set; once you click on this button, the next question will be displayed, and you will not be able to change the answer to the previous question.

Abstract Format
The abstract item format includes a summary of an experiment or clinical investigation presented in a manner commonly encountered by a physician, eg, as an abstract that accompanies a research report in a medical journal. Examinees must interpret the abstract in order to answer questions on various topics, including

  • Decisions about care of an individual patient
  • Biostatistics/epidemiology
  • Pharmacology/therapeutics
  • Use of diagnostic studies

See Example Abstract Item