USMLE Step 2 CK Content Outline 2026: Disciplines, Systems, and Task Domains
Direct answer: what does the 2026 Step 2 CK content outline cover?
The current Step 2 CK blueprint is multidimensional. USMLE organizes exam content through an integrated outline of general principles and organ-system categories, a Step 2 CK-specific physician tasks/competencies specification, and clinical-science classifications. The live Step 2 CK specifications give percentage ranges for 15 system/discipline rows, 12 task/competency rows, and five clinical-science groupings. Clinical-science totals can exceed 100% because an item may be classified to more than one clinical science. USMLE: Step 2 CK Content Outline & Specifications
The integrated 2026 USMLE Content Outline itself contains 18 major categories. The Step 2 CK weighting table combines some of those categories for reporting—for example, Blood & Lymphoreticular with Immune, and Musculoskeletal with Skin & Subcutaneous Tissue—and also includes Nutrition as a discipline. USMLE states that Nutrition-coded items are also coded to one of the system categories. USMLE Content Outline (2026) and Step 2 CK specifications
The three classification lenses behind Step 2 CK content
USMLE says all Step examinations use a common integrated content outline, while each Step has its own emphasis and specifications. For Step 2 CK, that means a question is not best understood as belonging to only “medicine” or only “cardiology.” The blueprint can classify the same item through different dimensions: its integrated content category, the physician task or competency being assessed, and its clinical-science discipline coding. USMLE Content Outline (2026) USMLE Physician Tasks/Competencies
The common physician-tasks document groups competencies under Medical Knowledge/Scientific Concepts; Patient Care: Diagnosis; Patient Care: Management; Communication; Professionalism, including legal and ethical issues; Systems-based Practice, including Patient Safety; and Practice-based Learning. The Step 2 CK-specific table then identifies the task categories that receive explicit Step 2 CK percentage specifications. The common outline should therefore be read alongside—not substituted for—the Step 2 CK table. USMLE Physician Tasks/Competencies
Step 2 CK system and discipline specifications for 2026
These are the current ranges published on the Step 2 CK content page. USMLE notes that percentages are subject to change at any time, so the official page remains the controlling reference. Human Development includes normal age-related findings and care of the well patient. Official Step 2 CK specifications
| System or discipline | Range |
|---|---|
| Nutrition | 15–20% |
| Social Sciences: legal/ethical issues, professionalism, systems-based practice & patient safety | 10–15% |
| Renal & Urinary System & Reproductive Systems | 7–13% |
| Cardiovascular System | 6–12% |
| Musculoskeletal System / Skin & Subcutaneous Tissue | 6–12% |
| Behavioral Health | 5–10% |
| Blood & Lymphoreticular / Immune Systems | 5–10% |
| Gastrointestinal System | 5–10% |
| Nervous System & Special Senses | 5–10% |
| Respiratory System | 5–10% |
| Multisystem Processes & Disorders | 4–8% |
| Endocrine System | 3–7% |
| Pregnancy, Childbirth & the Puerperium | 3–7% |
| Biostatistics & Epidemiology / Population Health / Interpretation of Medical Literature | 3–5% |
| Human Development | 2–4% |
Two details matter for interpreting this table. First, Nutrition is listed as a discipline rather than one of the 18 integrated content-outline categories. USMLE explicitly says a Nutrition item is also coded to a system category; its example is routine preventive care involving dietary counseling, coded to both Human Development and Nutrition. Second, the table uses combined rows for some content areas even though the underlying integrated outline lists them separately. USMLE Step 2 CK content specifications
What are the 18 integrated content categories?
The 2026 public-release USMLE Content Outline lists the following 18 categories. They provide the shared organizational structure across the USMLE sequence; no single Step is expected to include every topic listed in the full outline. USMLE Content Outline (2026)
- Human Development
- Immune System
- Blood & Lymphoreticular System
- Behavioral Health
- Nervous System & Special Senses
- Skin & Subcutaneous Tissue
- Musculoskeletal System
- Cardiovascular System
- Respiratory System
- Gastrointestinal System
- Renal & Urinary System
- Pregnancy, Childbirth, & the Puerperium
- Female and Transgender Reproductive System & Breast
- Male and Transgender Reproductive System
- Endocrine System
- Multisystem Processes & Disorders
- Biostatistics, Epidemiology/Population Health, & Interpretation of the Medical Literature
- Social Sciences
Within organ-system sections, USMLE describes content in terms of normal and abnormal processes, including principles of therapy. It also cautions that the diseases, symptoms, and examples printed in the outline are examples rather than an exhaustive universe of possible tested content. The program says it continually reviews content for relevance as medical practice and guidelines evolve. USMLE Content Outline (2026)
Step 2 CK physician task and competency domains
USMLE describes physician tasks and competencies as an additional organizing construct for Step 2 CK and states that each test question is constructed to assess one of the competencies in the Step 2 CK specification table. The current ranges are: USMLE Step 2 CK physician task/competency specifications
| Competency | Range |
|---|---|
| Patient Care: Diagnosis | 16–20% |
| Patient Care: Laboratory/Diagnostic Studies | 13–17% |
| Patient Care: Mixed Management | 12–16% |
| Patient Care: Pharmacotherapy | 8–12% |
| Patient Care: Clinical Interventions | 6–10% |
| Patient Care: Health Maintenance/Disease Prevention | 5–10% |
| Patient Care: Prognosis/Outcome | 5–9% |
| Systems-based Practice & Patient Safety | 5–7% |
| Professionalism | 5–7% |
| Practice-based Learning & Improvement | 3–5% |
| Medical Knowledge: Applying Foundational Science Concepts | 0%* |
| Patient Care: History and Physical Exam | 0%** |
* Applying Foundational Science Concepts: the Step 2 CK table assigns this category 0% as a standalone task, but USMLE states that patient-care items may also assess knowledge of underlying foundational science concepts. ** History and Physical Exam: the Step 2 CK table assigns this category 0%; USMLE states those competencies are covered in Step 1 and Step 3 examinations. Official Step 2 CK task specifications
The broader task document clarifies what the labels mean. Laboratory/Diagnostic Studies includes selecting, interpreting, or predicting study results; Diagnosis includes formulating the most likely diagnosis; Prognosis/Outcome addresses factors affecting expected course or complications; and management domains distinguish prevention, pharmacotherapy, clinical interventions, and mixed-management choices. USMLE Physician Tasks/Competencies
Clinical-science discipline groupings
Step 2 CK also classifies content by traditionally defined clinical sciences. USMLE explicitly says these items are deliberately integrative and that many items are classified to more than one clinical science, which is why the totals add to more than 100%. USMLE Step 2 CK clinical-science specifications
| Clinical science | Range |
|---|---|
| Medicine | 55–65% |
| Pediatrics | 17–27% |
| Obstetrics & Gynecology | 10–20% |
| Psychiatry | 10–15% |
| Surgery | 5–15% |
These are classification ranges, not a claim that every question belongs to exactly one clerkship bucket. A single integrated clinical item may carry more than one clinical-science classification while still being constructed around a specific physician task and a content-outline category. That is the core reason the Step 2 CK blueprint should be read as a matrix rather than as three independent lists.
How multidimensional categorization works
- Integrated content: the item is organized within the shared USMLE content-outline structure of general principles and organ systems.
- Task/competency: the Step 2 CK design assigns the item to a physician task or competency from the Step-specific specification.
- Clinical science: the item may be classified to one or more clinical-science disciplines; these labels can overlap.
- Nutrition cross-coding: when an item is coded to Nutrition, USMLE says it also receives a system content code.
This explains why a content-outline percentage is not the same thing as a question-type percentage or a clerkship-only breakdown. The blueprint is designed to integrate the clinical topic with what the physician is being asked to do.
Content outline versus format, scoring, scheduling, and eligibility
This page answers what content is categorized and weighted. It does not provide the test-day block schedule or question-format details; those belong to exam-format coverage and the official Step 2 CK page. It does not state score-report rules or score interpretation; use USMLE Examination Results and Scoring. It does not reproduce eligibility rules or scheduling procedures; use the current USMLE eligibility guidance, applying and scheduling guidance, and the applicable Bulletin of Information.
It also does not provide individualized study, medical, licensing, or career advice. Percentage ranges describe the examination blueprint; they do not predict an individual examinee’s performance or prescribe how any person should allocate study time.
Frequently asked questions
Does Step 2 CK use one content outline or several?
USMLE uses a common integrated content outline across the Step examinations plus a common physician tasks/competencies outline. Each Step then has Step-specific specifications indicating which areas are emphasized. Step 2 CK also publishes clinical-science classification ranges. USMLE Content Outline Step 2 CK specifications
Why do the clinical-science percentages add to more than 100%?
Because USMLE says many Step 2 CK items are classified to more than one clinical science. The clinical-science table is intentionally overlapping rather than mutually exclusive. USMLE clinical-science specifications
Is Nutrition a separate Step 2 CK system?
USMLE lists Nutrition as a discipline in the Step 2 CK system/discipline table at 15–20%. It also states that Nutrition-coded items are coded to a system content category from the integrated outline. USMLE Step 2 CK specifications
Does a 0% task mean foundational science can never appear?
No. The Step 2 CK table assigns 0% to “Medical Knowledge: Applying Foundational Science Concepts” as a standalone task, while USMLE explicitly notes that patient-care items may also assess the underlying foundational science. USMLE task specifications
Can the official percentage ranges change?
Yes. USMLE marks the Step 2 CK percentage tables as subject to change at any time. Check the live official specification page if you need the current controlling ranges. USMLE Step 2 CK Content Outline & Specifications
Editorial update note
Reviewed August 29, 2026. KOTC checked the live USMLE Step 2 CK specifications, the 2026 public-release integrated Content Outline, and the current USMLE Physician Tasks/Competencies document. The ranges above match the official Step 2 CK page as reviewed. No exam-format values are reproduced here so this article remains limited to content-outline intent.
Independent-publisher disclosure: King of the Curve is an independent test-prep publisher and is not affiliated with, endorsed by, or sponsored by USMLE, FSMB, or NBME. USMLE is a joint program of FSMB and NBME; official program information should be confirmed through the official sources linked in this article. USMLE: About the program
