This guide may be used as a framework in preparing for shelf exams during the clinical years of medical school. Everyone’s learning style and preferences differ slightly, so please adapt my recommendations to best fit your educational needs. I repeated clerkship year for subpar shelf exam performance, then went on to pass every subsequent shelf exam and USMLE Steps 1/2; if your academic situation is similar, this advice may resonate with you.
1. What is the exam breakdown?
The NBME publishes a “content outline” for each subject exam that may be found via https://www.nbme.org/examinees/subject-exams. Click on “clinical science” then whichever rotation you’re on. Most topics have similar weightings but some (e.g. cardiology for internal medicine) have over three times more than the others, so you may allocate your time accordingly. There are free accompanying “sample questions” as well with answers but no explanations.
2. Which practice test best reflects the shelf exam?
While QBanks are excellent, I believe the NBME self assessment is a better reflection of the shelf. The self assessments are 50 question practice tests with accompanying answers that cost $20 and are accessible via https://www.nbme.org/examinees/nbme-self-assessments/clinical-mastery-series. Some schools (e.g. USUHS) provide you access to one for free via a voucher code at the start of a rotation. If there are four total self-assessments for one subject, you may space them out evenly over the course of the rotation or take them all the week or two before the shelf exam to assess your knowledge, but more importantly use them as a learning tool. They predicted my shelf score well for most rotations, but were off by up to 16% on other rotations, so do not be discouraged or overconfident based on your score. Sometimes, these questions appear almost verbatim on the real shelf.
3. What is the best QBank?
The best QBank is the one you use regularly and completely. Some schools provide free QBanks (e.g. USUHS provides BoardVitals via the LRC website). My #1 recommendation is UWorld as it’s usually the “gold standard”. Others (Kaplan, Amboss) are fine as well.
4. How do I use a QBank?
a) Allocating — Divide the number of questions in UWorld for that particular subject by the number of days or weeks for that rotation then try to hit that target. For instance, 1600 IM questions (inpatient + ambulatory sections in UWorld) is a lot, but 23 a day or 160 a week over the course of a 10 week rotation is certainly reasonable. Adjust based on your clinical obligations (e.g. lighter clinic days vs longer inpatient days when taking call). Consider performing both 10–20 questions daily and 40 or 80 questions back to back once a week (or preferably near the exam) to work on pacing/attention span. Otherwise, 40 question sets and reviews can be tedious/boring if done daily.
b) Timing — Do questions before the shift starts, throughout the day if you have downtime, after the shift, and/or on days off. Bottom line, choose a time and location where you can be fully focused on your practice questions, not multitasking. At the same time, give yourself some grace on days off and don’t study 8–12 hours like you may otherwise do if you were in pre-clerkship. Hospital hours can be draining, especially if on a rotation you have little interest in, so use time off to rejuvinate your spirit as well.
c) Testing — I recommend answering questions in timed, test mode where you see the answers after the exam is over and practice your pacing in closed-book manner as if this was the real shelf exam. When you see your score, do not panic! I got 10–15% correct starting off a rotation and improved to 60–70% correct closer to the exam date, sometimes still scoring 40–50% correct if the question set was particularly challenging. UWorld lists the mean performance for the particular question set you selected … ignore it! Some people use this platform in group study sessions, with open book/internet, or before Step 2 when they’ve already completed a year of clinicals. Bottom line, don’t compare yourself to others. There are pros/cons to selecting random questions spanning all topics vs targeting studying in a single topic (e.g. cardiology for IM as it’s highly tested). Choose what is right for you given the circumstances.
d) Reviewing — Aim to spend about 2x the time reviewing the question set as you did completing it in the first place (e.g. 40 questions at 90 seconds per question takes 1 hour to complete with up to 2 hours review time, so 3 hours total). As previously mentioned, I think this is why shorter question bursts are more reasonable as 15 questions takes just over an hour total (22.5 minutes testing, 45 minutes review), and this better accommodates our attention span. When you first start, it may take substantially longer to review a section. To help be more efficient, consider implementing a timer with periodic alarms to minimize spacing out/going off on tangents. When reviewing each question, first scroll to the bottom and read the key takeaways. Next, if you don’t understand the question fully or want more detail about why the correct answer is right or why the incorrect answers are wrong, you may read the entirety of OR specific portions of the answer explanation. Frankly, reading the entire explanation word for word can be overwhelming and you’re unlikely to retain everything. You know yourself better than I do. Kindly don’t cheat yourself into thinking you understand something that you don’t. At the same time, it’s ok to occasionally spend extra time fully grasping the basics for a clinically high yield disease process.
e) Memorizing — Some people use Anki alone or alongside UWorld to learn and remember concepts. There are excellent premade decks (WiWa, Dorian, Zanki, or the infamous AnKing). However, I found Anki to detract from my 80% rule listed below and I didn’t learn best in this manner, so the pay-off on my shelf was minimal. I used Anki sparingly for high yield concepts I repeatedly forgot or particularly struggled with, but otherwise would “mark” questions I wanted to repeat before my shelf exam and do those again (time permitting, I think this method is more effective than trying to squeeze out 100–200 new questions before an exam when all of these could have concepts you also need to review with multiple passes before they’re solidified in your memory). One benefit of Anki is it’s typically easier to use throughout the duty day during bursts of downtime than practice questions in our noisy clinical workplace. Try it if you’d like and don’t be afraid to ditch it if it’s not working. Too many students fall into the trap of utilizing the same resources as top performers (discussed in online articles/videos or by classmates) just for the sake of copying, but not because you share a similar learning style. While memorization is still necessary for shelf exams, there is greater emphasis on understanding the basics/key info and then applying concepts (2nd/3rd order questions).
5. What about lectures, podcasts, textbooks (Harrisons), review books (e.g. Case Files), or other sources (e.g. UpToDate) for learning?
Some of these sources (particularly UpToDate) are excellent for learning more about patient’s medical diagnoses but are relatively passive forms of learning and rarely translate well to the shelf exam. I recommend devoting at least 80% of study time to practice questions, with the remaining 20% for questions or a mix/match of the resources listed above. I utilized this approach and increased my shelf scores from 50s–60s% up to the class mean. Your colleagues may do zero questions and perform in the top 10%; kudos to them, they are likely good test takers, but you can still improve and should not necessarily follow in their footsteps when it comes to exam prep. Your school may provide an overwhelming amount of supplemental resources or required reading; utilize what is helpful and forgo the rest. You are responsible for your success, so don’t blame anyone else if you followed or didn’t follow the school’s advice and failed a shelf exam.
6) Who can help me?
I informed the site director at each of my clerkships that I struggled with pre-clerkship exams and asked if a volunteer resident is willing to spend 30–45 minutes per week with me going through practice questions. The goal was not just improving clinical knowledge, but also test taking approach. Residents add more insight than just an answer explanation because they can relate vignettes or diagnoses to patients they’ve seen in real life so you better understand the concepts. Bottom line, be specific when asking for help. Giving someone expectations for both time commitment, learning approach (e.g. QBank), and realistic goals is typically more palatable for residents than vaguely asking them to teach you everything you need to know for the shelf exam. Be reasonable as well … an attending may not have this spare time or interest, an intern/resident may. Ask enough people and eventually you’ll find someone willing to help.
Disclaimer: The views expressed in this article are those of the author and do not reflect the official policy or position of the U.S. Army, Department of Defense, U.S. Government, or Uniformed Services University of the Health Sciences.
