Subspecialty Certification Exam


To be eligible for certification in Mohs Micrographic Surgery, candidates must meet the criteria below:

  • Be a graduate of a COCA-accredited college of osteopathic medicine.
  • Satisfactorily complete a one-year internship in an AOA approved training program.
  • Satisfactorily complete three years of AOA-approved training in dermatology.
  • Satisfactorily complete a one-year fellowship program in MMS (AOA- or ACMS-approved) or Procedural Dermatology (AOA-approved). Active participation in a minimum of 400 cases of MMS during the training period is required.
    • If you did not complete an MMS fellowship, you may be eligible for certification under the clinical practice pathway if you have completed the “Fundamentals of Mohs Surgery Course” sponsored by the American Society for Mohs Surgery, have attained fellowship status within that organization, and have had a minimum of 200 cases of MMS performed in clinical practice within the last two years.
  • Be board certified in dermatology by the AOBD.
  • Be able to perform the complete MMS procedure; work in direct communication with the Mohs histotechnician; formally evaluate and interpret the histologic sections and map the findings appropriately; and be registered to perform the Mohs procedure under CLIA regulations.
  • Hold an active license to practice in a state or territory.
  • Adhere to the AOA Code of Ethics.


At the time of application, you must submit the following to the AOBD:

  • A copy of your medical license.
  • A copy of your fellowship certificate or diploma and the complete surgical case log with 400 cases from the fellowship program within a period of time not to exceed two years from date of examination.
    • If applying under the clinical practice pathway, you must submit a log documenting a minimum of 200 cases of MMS performed in clinical practice within a period of time not to exceed two years from date of examination. The log must indicate a confidential method of patient identification, the tumor type, preoperative tumor size, tumor location, number of stages and postoperative wound size.
  • A copy of your CLIA laboratory certificate.
  • A formal letter indicating the nature of your training in MMS.
  • All corresponding histologic slides.

Exam Fees

An application fee of $1,800 must be submitted with your completed application, either by check or credit card. No application will be considered complete until all fees have been paid. No amount of the examination fee paid shall be returned after the application has been processed. If an applicant fails the written or slide portion of the exam, the fee for re-examination is $900. If they fail both parts of the exam, the fee for re-examination is $1,800.

Exam Dates and Deadlines

The Mohs Micrographic Surgery Written & Practical Exam is offered once per year, generally every fall. Applications are due August 1 of each exam year.

Exam Content Outline

The Mohs Micrographic Surgery examination has two parts: a written exam and a practical exam.

  • The written exam includes testing on several areas, such as tumor biology and cutaneous oncology indications for MMS surgical technique, surgical anatomy, local and regional anesthesia, preoperative evaluation, histological technique, wound care and wound healing, dermatopathology, surgical complications, and instrumentation. The core references used to construct the examination include the standard texts on Mohs Surgery, Dermatology, and Dermatologic Surgery as well as peer-reviewed journals on dermatology, dermatologic surgery, cutaneous oncology and reconstruction, and additional references.
  • The practical exam is an evaluation of six submitted representative cases (as stated above). As deemed necessary, any given applicant may be asked to provide oral explanation of any cases or answer specific questions regarding a case as part of the overall examination.

Exam Scoring

Scoring Criteria

AOA reports candidates’ certification results using standardized scaled scores. Scaled scores are more valid and reliable compared to raw scores and make scores comparable across different forms of the exam. The AOA reports scores on a 200 to 800-point scale with a scaled score of 500 or higher required to pass.

  • A scaled score of 500 represents the minimum level of knowledge and skill necessary to pass the exam as established by AOA Certifying Boards.
  • The highest possible scaled score is 800.
  • The lowest possible scaled score is 200.
  • Overall scores are based on the total number of items answered correctly, regardless of content area.

Results by Content Area

  • When possible, a breakdown of exam scores by content area is provided to help you identify your areas of strength and areas that may need more development.
  • The number of items for each content area indicates the relative amount of test questions on the exam for that content area.
  • Content area scores are not weighted to calculate your overall score; each content area is scored separately after the overall analysis is complete.

Exam Failure

Failure to supply the required cases for the practical exam will disqualify the candidate from sitting for the written exam. Candidates who fail the practical section will need to submit new cases not previously submitted. No feedback will be given after the MOHS slides are reviewed and scored.