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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 accessed from 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.

Step 2 CK consists of multiple-choice questions (MCQs), also known as items, created by USMLE committees composed of faculty members, investigators, and clinicians with recognized prominence in their respective fields. Committee members are selected to provide broad representation from the academic, practice, and licensing communities across the United States and Canada.

Step 2 CK focuses 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.

What new content appeared on Step 2 CK exams administered after the exam was updated in October 2020?

No new content was assessed in Step 2 CK exams administered after the exam was updated in November 2020. Examinees who tested after the November 2020 update saw a small increase in the number of items that assess knowledge of Professionalism, Legal/Ethical, and Patient Safety; this content has been included on the Step 2 CK exam for many years.

You can see representative items in these categories: Step 2 CK Patient Safety and Step 2 CK Professionalism.

Content Outline

All USMLE examinations are constructed from an integrated content outline, which organizes content 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.

Step 2 CK 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 each USMLE Step examination, overall content coverage is comparable among the various examination forms that will be taken by 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 Step 2 CK General Principles category includes normal and abnormal processes that are not limited to specific organ systems.

Physician Tasks/Competencies

An additional organizing construct for Step 2 CK design is physician tasks and competencies. Each test question is constructed to assess 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 are covered in Step 1 and Step 3 examinations.


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

Table 3: Step 2 CK Discipline Specifications*

Range, %
Obstetrics & Gynecology

* Percentages are subject to change at any time.

More than 100 sample Step 2 CK test questions are available in both PDF format and as an interactive testing experience.

Below are examples of different types of competencies tested on the Step 2 CK examination.

Example Question: Patient Care: Diagnosis - Laboratory/Diagnostic Studies

A 17-year-old girl comes to the office for an examination prior to entering college. She reports that she feels well but is nervous about leaving home for the first time. She states that she has tried to diet to improve her appearance but that food restriction often "backfires" because she becomes hungry and then engages in episodes of binge eating. She reports a loss of control during these episodes, saying, "It's like I stop thinking at all and before I know it, I have eaten two pizzas." She induces vomiting several times during each binge and has developed a pattern of binging and purging every evening. She has no history of serious illness and takes no medications. She is 165 cm (5 ft 5 in) tall and weighs 57 kg (125 lb); BMI is 21 kg/m2. Vital signs are within normal limits. Physical examination shows dry mucous membranes, erosion of enamel on the lingual surface of the front teeth, and hypertrophy of the parotid gland. Serum studies are most likely to show which of the following sets of findings in this patient?






















(Answer: B)

Example Question: Patient Care: Health Maintenance/Disease Prevention & Surveillance

A 21-year-old woman comes to the office for counseling prior to conception. She is recently married and would like to conceive within the next year. She does not eat meat, fish, or dairy products and wishes to decrease the risks of her diet on her baby. Menses occur at regular 28-day intervals and last 5 days. She does not smoke or drink alcohol. She takes no medications. She is 157 cm (5 ft 2 in) tall and weighs 50 kg (110 lb); BMI is 20 kg/m2. Physical examination shows no abnormalities. Pelvic examination shows a normal appearing vagina, cervix, uterus, and adnexa. Which of the following is most likely to decrease the risk of fetal anomalies in this patient?

  • Adjusting diet to include more sources of protein during the first trimester
  • Beginning folic acid supplementation prior to conception
  • Calcium supplementation during the first trimester
  • Iron supplementation during the first trimester
  • Soy protein shakes throughout pregnancy and lactation
  • Randomized clinical trial

(Answer: B)

Example Question: Professionalism

Three days after hospitalization for diabetic ketoacidosis, an 87-year-old woman refuses insulin injections. She says that her medical condition has declined so much that she no longer wishes to go on living; she is nearly blind and will likely require bilateral leg amputations. She reports that she has always been an active person and does not see how her life will be of value anymore. She has no family and most of her friends are sick or deceased. On mental status examination, she is alert and cooperative. She accurately describes her medical history and understands the consequences of refusing insulin. There is no evidence of depression. She dismisses any attempts by the physician to change her mind, saying that the physician is too young to understand her situation. She says, "I know I will die, and this is what I want." Which of the following is the most appropriate next step in management?

  • Discharge the patient after she has signed an "against medical advice" form
  • Seek a court order to appoint a legal guardian
  • Offer insulin but allow the patient to refuse it
  • Admit to the psychiatric unit
  • Administer insulin against the patient's wishes

(Answer: C)

Example Question: Patient Safety

A 45-year-old woman is hospitalized for management of Staphylococcus aureus endocarditis with persistent bacteremia. The patient is discussed during interdisciplinary rounds, which includes physicians, nurses, pharmacists, and social workers. During rounds, a pharmacy student notices that the patient missed two doses of her scheduled antibiotic last week but is unsure why. The physician and nurse are unaware of these missed doses, and the student does not mention her observation. Which of the following measures is most likely to improve communication within this interdisciplinary health care team?

  • Conduct interdisciplinary rounds in a quieter location
  • Encourage questions from all team members
  • Implement a checklist for standardizing patient rounds
  • Use computers during rounds to review medications

(Answer: B)


  • 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.

Patient Scenario Formats

Patient scenarios for any Single Item or Sequential Item Set may be provided in either Vignette (paragraph) format, or in Chart/Tabular format. Test items using the chart/tabular format are designed to resemble patient charts but are not intended to be an exact representation of a patient chart. Questions written in chart/tabular format will contain relevant patient information in list form, organized in clearly marked sections for ease of review. Familiar medical abbreviations may be used within chart/tabular format questions.

Single-Item Questions

A single patient-centered vignette is associated with one question followed by four or more response options. The response options are lettered (ie, A, B, C, D, E). A portion of the questions involves interpretation of graphic or pictorial materials. You are required to select the best answer to the question. Other options may be partially correct, but there is only ONE BEST answer. This is the traditional, most frequently used multiple-choice question format on the examination.

Example Question 1

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)

Example Question 2

Patient Information
Age: 18 years
Gender: F, self-identified
Ethnicity: unspecified
Site of Care: emergency department

Reason for Visit/Chief Concern: "My roommate took a lot of pills and said she wanted to die."

History of Present Illness:
•   patient brought by ambulance 2 hours after a suspected acetaminophen overdose
•   roommate had returned to their dorm and found the patient distraught; patient was holding an empty bottle of acetaminophen and said, "I just want to die."
•   roommate estimates patient consumed 20 to 30 tablets of 500-mg acetaminophen

Past Medical History:
•   generalized anxiety disorder
•   major depressive disorder

•   citalopram

•   no known drug allergies

Family History:
•   noncontributory

Physical Examination

Temp Pulse Resp BP O2 Sat Ht Wt BMI
89/min 16/min 108/59 mm Hg 99%
on RA
170 cm
(5 ft 7 in)
63 kg
(140 lb)
22 kg/m2

•   Appearance: awake and alert but distraught and fearful; patient says, "This was totally stupid."
•   Pulmonary: clear lung fields
•   Cardiac: regular rhythm; S1 and S2, with an early systolic murmur
•   Abdominal: soft and nontender; liver and spleen cannot be palpated
•   Neurologic: no abnormalities; fully oriented

Question: In addition to obtaining serum acetaminophen concentration, which of the following is the most appropriate next step in management?

  1. Administer N-acetylcysteine
  2. Arrange hemodialysis
  3. Gastric lavage
  4. Initiate sodium bicarbonate infusion

(Answer: A)

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.

Example Question 1

A 35-year-old woman is brought to the emergency department because of worsening pain and swelling of her right knee for the past 2 days. She has been taking acetaminophen for the knee pain during the past 2 days, but the pain is worse today. She has not had any trauma to the knee or any previous problems with her joints. She is otherwise healthy and she currently takes an oral contraceptive. She is sexually active and has a 10-year-old son who lives with her. She is a receptionist at a local hotel and she tells you she must stand often while working. She is 160 cm (5 ft 3 in) tall and weighs 52 kg (115 lb); BMI is 20 kg/m2. Temperature is 37.9°C (98.9°F). The right knee is erythematous, swollen, and tender; there is pain on movement. No other joints are affected. X-ray of the knee shows an effusion but no structural abnormalities of the joint.

Which of the following is the most appropriate next step in diagnosis?

  1. Arthrocentesis of the knee
  2. Blood cultures
  3. MRI of the knee
  4. Urine cultures

(Answer: A)

Arthrocentesis is done. The synovial fluid is cloudy. Gram stain is negative. Analysis of the synovial fluid shows a leukocyte count of 120,000/mm3 and 90% neutrophils. Which of the following is the most appropriate additional test on the synovial fluid?

  1. Culture for bacteria
  2. Glucose measurement
  3. Polarized light microscopy
  4. Protein level

(Answer: A)

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