CAQ-Nephrology

The American Osteopathic Board of Internal Medicine (AOBIM), an AOA specialty certifying board, administers the nephrology subspecialty credential. Applications, registrations, and results all flow through the Certification Portal linked from aobim.org, where you will also find the exam dates and deadlines page and board policies. Confirm eligibility requirements there before you submit anything.

AOBIM's published important-dates list shows Aug. 12-14, 2026 for the AOBIM Initial Certification Subspecialty Exams and the same Aug. 12-14, 2026 window for the AOBIM Subspecialty OCC (Recertification) Exams. Nephrology sits within the subspecialty group. Always recheck the Exam Dates & Deadlines page before booking travel or leave, since windows can be updated.

They are separate exam administrations that AOBIM schedules in the same August window. Initial certification is for physicians attaining the subspecialty credential for the first time. OCC (Osteopathic Continuous Certification) is the maintenance pathway for physicians already certified, and it includes four numbered components plus a longitudinal assessment taken through the Learning Portal. Choose the registration track that matches your current status.

AOBIM's public site does not publish an item count, time limit, or section structure for the nephrology subspecialty exam, so any number you see quoted online should be treated as unverified. Ask AOBIM directly, or check the candidate materials released with your registration confirmation, before you build a pacing plan around a specific figure.

Neither the passing standard nor the retake policy is published on the AOBIM public site, so treat both as unknowns and get them in writing from the board. Practically, that means budgeting study time as if you have one attempt: build a broad base first rather than gambling on a narrow high-yield list and a presumed retake.

Start with fluid, electrolyte, and acid-base physiology, because compensation formulas and anion-gap reasoning underpin nearly every other topic. Then move to acute kidney injury and critical care, where the differential and urine studies reuse that physiology. Follow with glomerular and tubulointerstitial disease and its pathology, then CKD, dialysis, and transplantation, and finish with hypertension and renal manifestations of systemic disease, which pulls from all the earlier blocks.

Recurring weaknesses are shallow acid-base interpretation (stopping at the primary disorder and missing the compensation or mixed picture), memorizing dialysis numbers without understanding clearance and prescription logic, shaky transplant immunosuppression and rejection timing, and pattern-matching glomerular pathology without linking it to serologies. Another common trap is ignoring hypertension and systemic disease because it feels less like "core" nephrology.

AOBIM maintains both a Remote Exam Preparation page and a Test Accommodations page, so remote delivery and accommodation requests are handled through the board rather than through a testing vendor you contact independently. Read both pages early, since accommodation requests typically carry their own deadlines that fall before the general registration cutoff.

AOBIM publishes an OMT Designation page describing an additional recognition tied to osteopathic manipulative treatment. Whether it applies to your subspecialty pathway and what documentation it requires is a board question, not something the nephrology pages spell out. If the designation matters for your practice or hospital privileges, ask AOBIM before the application cycle opens.