Step 2 CK Content Outline & Specifications

Content Description

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.


  • The term item is used to describe a test question in any format.
  • You must run the Step 2 CK interactive testing experience 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 tutorial in the Step 2 CK interactive testing experience.
  • The interactive testing experience includes 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.

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 Clinical Knowledge (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, %
Human Development** 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 Human Development topic includes Normal Age-Related Findings and Care of the Well Patient.

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 Tasks/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*

Competency Range, %
Medicine 50–60
Surgery 25–30
Pediatrics 20–25
Obstetrics & Gynecology 10–20
Psychiatry 10–15

* Percentages are subject to change at any time.