how many experimental questions on step 1

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How Many Questions Are On The USMLE Step 1?

Everything you need to know about usmle step 1 questions.

The USMLE Step 1 is taken by students at the end of their second year in medical school. The goal of the test is to determine whether you understand how to apply certain core concepts of the sciences that were covered during your first and second years in medical school. In this guide, we discuss the quantity and types of questions you should expect to see on the USMLE Step 1 exam.

USMLE Step 1—How Many Questions Total?

The USMLE Step 1 test is a one-day exam spread over eight hours divided into seven 60-minute blocks or sections, depending on which term you would like to use. There is also a 45-minute break and a 15-minute optional tutorial as well.

The number of questions for each block can vary, but there will never be more than 40 questions per block. The total number of questions on the exam will not exceed the 280 mark .

What Types Of Questions Are On The USMLE Step 1?

Questions on the test will generally require several steps of knowledge and reasoning to answer.

The questions will often require that test takers do one or more of the following: (1) apply basic science knowledge to clinical problems; (2) identify gross and microscopic pathologic and normal specimens; and (3) interpret graphic and tabular material to answer questions .

In some cases, there will be a single, best answer. Other times, a problem will include a story about a patient followed by one or more questions.

What Topics Do The USMLE Step 1 Questions Cover?

The questions on the USMLE Step 1 cover a range of disciplines and topics. This includes anatomy, behavioral sciences, biochemistry, biostatistics, epidemiology, microbiology, pathology, pharmacology, and physiology.

It can also include interdisciplinary topics including aging, genetics, immunology, nutrition, and molecular and cellular biology.

Sample USMLE Step 1 Questions

Question 1 : In a study of prokaryotic metabolism, growth rates of E. coli are viewed in the setting of various nutrient environments. The bacteria grow at a stable rate in a glucose-rich environment. When transitioned to a lactose-rich environment, growth slows at first but resumes following a short delay. What is the mechanism of this shift in nutrient metabolism ?

(A) Metabolite inhibition of a transcription repressor (B) Metabolite stimulation of a transcription repressor (C) Metabolite inhibition of a translation repressor (D) Metabolite stimulation of a translation repressor

Question 2 : A 5-year-old boy is treated for a cough that has been present for the last 7 weeks. He was seen by his pediatrician 6 weeks ago for a low-grade fever, cough, and runny nose. The coughing spells last for minutes at a time and are usually associated with post-tussive emesis. His mother reports that he has not had any immunizations since 5 months of age. His vital signs are normal and his physical examination is commonplace. Laboratory evaluation reveals an absolute lymphocyte count of 21,000 lymphocytes/microL. Which of the following is the most appropriate treatment for this boy’s symptoms ?

(A) Azithromycin (B) Amoxycillin (C) Isoniazid (D) Oseltamivir

To help you prepare for questions like these, you may want to consider signing up for a prep course , which typically include a multitude of USMLE study materials , including video lessons, live classes, and of course, additional practice questions.

A couple top-rated USMLE prep courses include Kaplan , PASS Program , and Med School Bootcamp . These courses will get you prepared to answer any question that will likely appear on Step 1 of the USMLE exam.

How many questions per block in USMLE Step 1?

The number of questions you will be asked per block on the USMLE Step 1 exam will vary. However, in most cases, each block typically contains 30 to 40 questions.

How many questions on USMLE Step 1 are experimental?

The exact number of experimental questions asked on the USMLE step 1 is unknown. However, it is estimated that approximately 15% to 20% of questions are considered experimental and do not count towards your overall score.

What percentage of questions must you answer correctly to pass the USMLE Step 1?

In order to pass the USMLE Step 1, you must answer approximately 60% of questions correctly. In numerical terms, if there are 280 questions in total, you must answer at least 168 questions correctly.

What is the best way to answer USMLE Step 1 questions?

Most USMLE tutors agree that reading the last line of the question first is often the best way to answer USMLE questions. That way you know what to look for as you begin to read questions that are more lengthy.

USMLE Step 1: Everything You Need to Know as You Prepare

The USMLE Step 1 is among the most pivotal milestones of medical school. It serves as the culmination of your preclinical education and represents your transition from preclinical to clinical training. The exam is transitioning to a pass-fail format “no earlier than January 1, 2022.” However, at present, how you score is often a primary factor used by medical school deans and residency program directors to decide if you can contend for a slot in one of the more competitive specialties or top programs. It’s big and its outcome can have lifelong consequences. USMLE Step 1 preparation should be taken seriously. Lawyers have the bar, doctors have Step 1. 

Does this mean that you should panic as your prepare for Step 1? No! This exam is not for the faint of heart, but you will become familiar with its format and question style throughout your preclinical courses by means of NBME exams, question banks, and  First Aid to the USMLE Step 1 . If you take the time to develop good test-taking habits, focus during early course work, and decide how you best learn and retain information, you can conquer this test and get a fantastic jump start on your career.

Below is a synopsis of the Step 1 format and structure. While changes may be on the way for this test, the overwhelming likelihood is that the format of this exam will largely stay unchanged.

What is the USMLE Step 1?

The United States Medical Licensing Exam (USMLE) Step 1, most commonly referred to simply as “Step 1,” is the first of three national licensing exams that physicians must pass to practice independently. Step 1 is taken at the completion of pre-clinical training, usually around the second year of medical school. Step 2 is taken by fourth-year medical students prior to graduation, and Step 3 must be completed before the end of PGY-2 of residency. All three exams are taken at a Prometric testing center, which is a test-taking facility that ensures that exam administrations are standardized and secure. 

Step 1 is the first test that distinguishes physician candidates from other health sciences fields. It does this by asking the physician candidate to bridge clinical and pre-clinical scenarios via multi-step questions, which require the synthesis of a “most likely diagnosis” and the knowledge of its basic underlying disease mechanisms. Hence, on this exam you are a literal “doctor on paper.” 

In addition to its guidance of candidates in rudimentary clinical thought, Step 1 is also the only standardized exam for which the scores are consistently available for every residency candidate, which makes it a powerful threshold and benchmarking tool for residency directors hoping to screen their applicant pool. Currently, Step 1 score thresholds are often used by top programs in more competitive specialties to artificially trim down the applicant pool. Even top applicants with poor Step 1 scores may be omitted from a program’s consideration. 

In the impending age of pass-fail scoring, a Step 1 failure is likely to be devastating to a residency applicant. Therefore, the onus to prepare for the exam properly will not change as the exam evolves. 

Step 1 Exam Content and Structure

Step 1 is an eight-hour exam that is subdivided into seven blocks of up to 40 questions each. You can take up to an hour per block, which means that on average each question should only be considered for about a minute and a half. If you finish a block early, any time saved can be “banked” for additional breaks above the 45 minutes available at the start of your exam. Although you cannot pause the exam while currently in a block, you can take breaks of any length that you’d like up to your maximum break time in between any blocks that you choose.

The USMLE provides a rough breakdown of the exam by organ system, competency, and discipline. A variety of concepts are tested throughout the exam, including physician communication, biostatistics, and gross anatomy. However, around half of the exam is classified as pathology, suggesting a focus on disease states and their underlying mechanisms. An exhaustive concept list is provided by the USMLE. However, it is inadvisable to study off of this list alone, as it weighs all concepts equally and does not permit appropriate selection and distillation of “high yield” concepts, which is done more proficiently through  First Aid to the USMLE Step 1  and USMLE question banks . 

A major advantage of this exam is the flexibility that it provides for self-directed  breaks . This lets you plan and practice your test-taking pace, and know that it can be applied during the real exam. Bring extra food for breaks! A tactic I used to use was to buy three bagels with my favorite toppings to store in my testing locker. Each of the three breaks I planned for was bagel time – nothing better than a little comfort food and carbo-loading mid-exam. Everyone relaxes differently, but definitely give some thought as to how you’ll break. With seven fast-paced blocks, everyone will deal with test fatigue of some sort.

How Many Questions are on Step 1?

A total of 280 questions are on the exam. This total includes non-scored “experimental” questions, which are not distinguished from the scored official questions. The exact number of unscored questions is not disclosed by the USMLE, although it has been  speculated  that roughly 25% of each exam is experimental (or 80 questions per test) . Experimental questions are being benchmarked for future iterations of the test, and are therefore not calculated into your exam score. That means that you shouldn’t fret if you don’t know the answer to every question – maybe that one was experimental!

How Long Do I Need to Study for the Exam?

It’s impossible to totally cover all of the material that will appear on Step 1 while studying. The material is too voluminous and dense. Instead, we must rely on high-quality question banks and review books to  distill material into “high yield” silos  for us. An example of high yield selection can be seen in microbiology. Rather than having to memorize every aspect of every parasite, worm, virus, and bacterium, the high yield approach permits conceptual highlighting of those aspects of microbes most likely to be tested. Don’t memorize every viral structure, just understand “key” RNA and DNA viruses. You only have finite brainpower and finite time, so don’t waste it!

Figuring Out How Long it Would Take You to Study for Step 1

How long it takes for you to process all of that test-relevant information relies on a few factors:

• How hard you studied during preclinical classes and how well you did on the NBME exams.  While the NBME should not be used as a finite indication that you will pass Step 1, it is similarly formatted and necessitates similar test-taking strategies. It also highlights similar high yield material to that found on Step 1. So while resting on your NBME scores is inadvisable, using them as a bellwether to indicate the need for future focus is very useful when planning your study strategies. 
• How you learn.  Flashcard “crammers” might build up a test knowledge base faster than people who only learn when they backwards-derive each concept from its basic mechanistic level to clinical fact. However,  cramming is less likely to produce long-term retention , so creating a long-term study schedule that “peaks on test day” is crucial.
• How confident you are.  You GOT THIS! This test is important, but so was your MCAT and you had to have done well on that to be accepted into medical school in the first place. Confident examinees will score better; albeit, confidence during an exam and overconfidence in preparation are completely different issues. You should be prepared to be humbled by the preparation process, but in turn approach the exam confidently.

Top 3 Things You Need to Know as You Prepare for USMLE Step 1

• Fatigue is real.  You will get tired. How you plan for and manage your fatigue will heavily influence your ultimate score. I managed fatigue by planning my snack breaks, ensuring that I never took more than two sections in a row, and that I always had something to eat before going back. Colleagues of mine took a short walk to reset their minds. Know yourself, know how you recover from fatigue, and embrace it on test day. 
• Worst case, you can push the test back.  Step 1 is offered on a rolling basis, and can be pushed back if you deem your preparation inadequate. I pushed my Step 1 back by six days because I felt mentally unprepared and made a slight adjustment to my study approach. I had the jitters and needed to get rid of them, so bought myself the time I needed to recalibrate – it wasn’t a long extension, but to me it was an eternity. On my new test date I showed up calm and happy. I am confident that rescheduling my exam improved my score. 
• Smile at the end, it’s OVER!  294 or 194: either way, a score between those numbers is a pass, and in 2022 your score above a passing mark will truly be irrelevant. Smile, celebrate, and move forward. You’re going to be a doctor, after all!

Written By:  Mitch Fourman, MD, Orthopaedic Surgery Resident, University of Pittsburgh

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What are Experimental Questions on the USMLE Step Exams?

As medical students, we all know that the USMLE board exams represent a gauntlet of tests that are part of the gateway to licensing and residencies. Yes, these exams are known to be notoriously difficult, and every med student will tell you that the struggle is real. Among the many challenges that the USMLE Step exams pose, there is one that catches many students off guard – the Experimental Questions. These questions, which might feel like mindboggling landmines on test day, are a topic of anxiety for those who are prepping.  So let’s take a moment to describe what these experimental questions are, why they exist, and how many you’re likely to see on test day.

Experimental Questions

Experimental questions have been a part of the USMLE Step exams for quite some time now. These questions are a means of testing the questions for their future inclusion in the exams. Essentially, these questions do not count towards your final score, but are instead used to develop and refine future exam questions. Experimental Questions are typically included in every section of the exam, and, sadly, there aren’t blinking neon lights identifying them for you.

The reason for the inclusion of experimental questions on Step 1 and Step 2 CK is quality assurance. The NBME is in charge of setting the standards for medical licensing and is responsible for ensuring that all medical students who pass the exams meet those standards. The USMLE Step exams are updated regularly to reflect changes in medical practice, research, and education, and to improve the safety and quality of patient care. The Experimental Questions that are included in the exams help the USMLE program keep up with these changes and are intended to help make future exams as fair and accurate as possible.

Experimental questions are not graded, and they do not affect your final score. This means that you should not spend any more time on them than you would on any other question. Focusing on getting as many correct answers as possible is important, rather than worrying about these sometimes sadistic items built in the NBME’s lab. Don’t feel discouraged if you come across a question that seems unusually difficult or unfamiliar – it could be an Experimental Question.  However, even if a question smells experimental to you, you still want to approach it with the same framework you use for every other question.

It is essential to note that experimental questions do not count towards your final score , because they are not easy. While they’re ostensibly designed to mimic the difficulty level of the exam questions, students report that they feel significantly harder. It is not uncommon for students to feel befuddled and lost when they encounter experimental items, a feeling that can quickly derail their exam performance if you don’t keep a level head. As medical students, it’s important to be aware of their existence and prepare yourself with the same level of intensity as you would for any other exam question.

How Many Experimental Questions Are on the USMLE Step 1 and USMLE Step 2 CK Exams?

Experimental questions can make up a substantial portion of the exam, but the exact number is generally not disclosed. Back in 2020, the  USMLE proposed a shortened version of the exam back in 2020, where they essentially would remove the experimental questions.  The changes would have reduced the number of Step 1 questions from 280 items to 200, while slimming Step 2 CK from 318 to 240.  These changes would have decreased the overall test time by two hours. But this proposal didn’t fly.

Nevertheless, the proposal revealed that roughly 25% of the questions on these exams are experimental .  So if you feel stumped every 4 questions, this might be the reason why.

Experimental questions are an integral part of the USMLE Step exams, even though they do not count towards your final score. As medical students, just be aware of their inclusion and be prepared to tackle them like any other exam question. And if you come across an unfamiliar or challenging question during Step 1 or Step 2 CK, remember that it could be an experimental question, take a deep breath and tackle it with confidence.

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