Core Competency Capstone for DOs

What is C3DO?

C3DO provides an assessment of the following osteopathic clinical skills competencies to a national standard:

• History building and hands-on physical examination skills
• Osteopathic clinical reasoning
• Interpersonal and communication skills, professionalism, and compassion in patient care
• Performance of osteopathic manipulative treatment (OMT)

These are evaluated through participation in a multi-station, modified Objective Structured Clinical Examination (OSCE) standardized patient-based assessment. It utilizes standardized assessment tools and training protocols, osteopathic physician examiners, and a national case bank aligned with the COMLEX-USA Blueprint. C3DO is developed through a national collaboration and is delivered locally at participating colleges of osteopathic medicine.

Why C3DO?

Following the indefinite suspension of the COMLEX-USA Level 2-PE, stakeholder input to the NBOME showed strong support in maintaining assessment of clinical skills at a national standard for the osteopathic medical profession. Maintaining such an assessment was seen not only as an essential element of licensure assessment for DOs, but as part of professional self-regulation to support quality care for our patients and an integral component to the distinctive practice of osteopathic medicine.

In addition, the American Osteopathic Association Commission on Osteopathic College Accreditation (COCA) specifies, “prior to graduation, all students must demonstrate osteopathic medical knowledge and osteopathic clinical skills…and meeting a national standard for osteopathic clinical skills competency assessments as required for licensure.”

The Core Competency Capstone for DOs (C3DO) assessment and the Comprehensive Competency Verification (CCV) were developed to meet this consensus and to safeguard patients. At its Midyear Meeting in June 2026, the NBOME Board of Directors approved prerequisites for C3DO and CCV, as well as the structure and requirements for completing CCV.

The C3DO assessment:

• Supports external assessment of clinical skills competency as required for licensure (see COCA Standards Element 11.4) and to a national standard.
• Offers a clinical skills credential for students on the official COMLEX-USA transcript.
• Provides faculty and staff development at the COM.
• Delivers valuable reporting to COMs—including performance metrics, clinical presentation data, and comparative insights—to inform continuous improvement, research, and quality assurance.

Cost Structure

The NBOME Board has approved the following fee structures for C3DO:

• COM Main Campus Annual Subscription: $30,000
• Additional Testing Site Annual Subscription: $15,000
• Student Registration: $275

Test Specifications

The cases presented within C3DO are common for DOs in the outpatient clinical setting and align with  Dimension 2 of the COMLEX-USA Blueprint: Clinical Presentations, shown below.

Since there are 10 clinical presentation categories in the blueprint and only six stations in the assessment, not all categories will be represented on each examination. Every candidate should see at least one case which is Community Health and Patient Presentations Related to Wellness, and two cases that are clinical presentations related to the Musculoskeletal System.

Skills Assessed in C3DO

Schedule

C3DO sessions are 3-4 hours in length. Each encounter time with the patient is 14 minutes, and there is an additional 6 minutes to complete the post-encounter questions.

Encounter timing is universal across administrations, but other components, such as onsite registration, orientation, transition between encounters, breaks, and refreshments (if any), are determined by each COM independently. Candidates should check with their COM for more information about the local schedule.