ABEM clinical decision-making cases, explained
The clinical decision-making (CDM) case is the classic single-patient encounter on the ABEM Certifying Exam. Here is what it is really testing, and how to practice it.
What the case looks like
One patient, worked through out loud
You take a single patient from the door to disposition with an examiner: gathering history, examining, ordering and interpreting the workup, treating, and deciding where the patient goes. You narrate your thinking the whole way.
It tests your reasoning, not just the answer
The case rewards how you get there — the dangerous causes you consider, the workup you justify, and the decisions you make — not only whether you name the final diagnosis. Say why you are doing what you are doing.
Ask broad before you ask narrow
Strong examinees open with the broad dangerous-cause workup for the complaint in front of them, then narrow as findings come back. Jumping straight to a pet diagnosis is how you miss the thing that actually matters.
Critical actions carry the case
Each case has a few must-do actions that change the outcome. Hitting those — and not fixating so hard on the diagnosis that you skip one — is what separates a pass from a miss.
Common traps
- Anchoring on one diagnosis early and never revisiting it as findings arrive.
- Ordering tests without saying why, so your reasoning goes uncredited.
- Spending so long on history that you never reach treatment and disposition.
- Skipping a critical action while chasing the perfect diagnosis.
How to practice it
The skill is verbalizing a clean workup under time — so practice out loud, one patient at a time, and compare your reasoning against a model answer. Pay attention to what you left unsaid: the dangerous cause you did not mention, the critical action you skipped.
PrepEM includes timed CDM cases with examiner prompts, real ECGs and imaging, and side-by-side answer review. See also the prioritization cases guide and how to pass the ABEM oral boards.