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How to Use NBMEs to Study for Step 2 CK

If you’re reading this post, you’ve probably already made it past the first big exam hurdle in your medical school career: USMLE Step 1.

Congratulations! Your thoughts are likely now turning to Step 2 Clinical Knowledge (CK) and Step 2 Clinical Skills (CS).

Let’s spend some time talking about how to use NBME practice exams in your study preparation for Step 2.

Which NBME practice exams should I use to prepare for USMLE Step 2 CK? 

Just like for Step 1, the National Board of Medical Examiners (NBME) writes a number of practice exams or “NBME Self-Assessments” to help prepare for Step 2 CK. These are multiple-choice exams that are supposed to test your knowledge from clinical clerkships. For Step 1, it was called “Comprehensive Basic Science Self-Assessment” or CBSE. The Step 2 CK version is called the “Comprehensive Clinical Science Self-Assessment” or CCSE.

NBME Comprehensive Clinical Science Self-Assessments for the CCSE:

  • NBME CCSE self-assessments are available on the NBME website:
  • Each CCSE is $60.
  • The exams are open to anyone and everyone, even if you haven’t ever signed up for Step 1 or Step 2 CK.
  • Right now there are 3 CCSE self-assessments available for purchase (NBME 6, 7, and 8).

How long are CCSE Self-Assessments?

Each CCSE assessment is:

  • 184 questions
  • 4 blocks
  • Each block is 1 hour 9 minutes

Compare this to Step 2 CK, which is:

  • Approximately 318 questions
  • 8 blocks
  • Each block is 1 hour

NBME Self-Assessments for the Clinical Science Mastery Series:

Let’s not forget that NBME also offers practice Shelf Exams, which you’ve probably already taken for your clinical clerkships. Confusingly these go by a different name on the NBME website: Self-Assessments for the Clinical Science Mastery Series.

Each Self-Assessment for the Clinical Science Mastery Series is:

  • 50 questions
  • 1 block
  • 1 hour 15 minutes total

Compare this to actual NBME Clinical Science Subject Exams (“Shelf Exams”), which are:

  • 110 questions
  • 1 block
  • 2 hours 45 minutes total

There are currently practice exams for the following subjects:

  • Clinical Neurology (4)
  • Emergency Medicine (1)
  • Family Medicine (2)
  • Medicine (4)
  • Obstetrics and Gynecology (4)
  • Pediatrics (4)
  • Psychiatry (3)
  • Surgery (4)

How do you use NBMEs for Step 2 CK prep? 

While UWorld questions are going to have the most bang for your buck, the NBME CCSEs are still useful for obtaining a scaled score that can predict your performance on Step 2 CK.

UWorld is the single most important Step 2 CK resource, especially when you have limited time, and some NBME questions are random and low-yield for Step 2 CK. That being said, NBMEs are absolutely still worth incorporating into your study plan.

Where do NBMEs fit into an optimal Step 2 CK study plan?

NBME practice tests should be taken at regular intervals throughout your Step 2 CK study period. The first NBME should be taken early on, as it serves as a baseline and can be used to chart your improvement over time. You don’t have to take the assessment on the first day of studying, but somewhere in the first 2-3 weeks is ideal.

You should then plan to take NBMEs every 1-2 weeks depending on the length of your study period. Try to take the NBMEs on the same day every week, in the same location. Don’t forget that there are also UWorld simulation exams for Step 2 CK that have great answer explanations. That makes for a total of 5 exams (3 NBME + 2 UWorld simulations) that can simulate the real testing environment.  

How should I interpret my NBME scores in regards to my Step 2 CK preparedness? 

First of all, it’s important to remember that you may not experience major improvements from each NBME self-assessment. Some students stay at the same level or even drop scores from one NBME to the next. An improvement of 5-10 points is fantastic and should be your goal.

Be sure to chart your performance over time by looking at your performance in each sub-field (pharmacology, etc). We recommend paying particular attention to pharmacology and microbiology, as these subjects are always emphasized on the exam.

Ideally, you want to be sure to see two consecutive scores 10 points above the current Step 2 CK passing score (209 as of April 2020) before sitting for the exam. That means that you should be scoring a 219 or higher on two exams. This buffer will make sure you enter the testing room with confidence!

Are there NBMEs available for Step 2 CS?

As you likely already know, the Step 2 Clinical Skills (CS) exam has been temporarily suspended due to the effects of the COVID-19 pandemic. There are no NBMEs for Step 2 CS, as the exam is based on real patient encounters rather than multiple choice questions.

Most students find First Aid for the USMLE Step 2 CS to be the most helpful guide in preparing for Step 2 CS. You should also use the official USMLE software several times to get a feel for the template you’ll use on exam day.