If you’re a medical student preparing for the USMLE Step 1, you already know how overwhelming the process can feel. Endless resources, heavy textbooks, and constant pressure to “know everything” can make studying exhausting. But there’s one preparation strategy that consistently makes the biggest difference: practicing with USMLE Step 1 sample questions.
In this blog, we’ll break down some high-yield USMLE Step 1 sample questions, explain the reasoning behind each answer, and give you tips to study smarter, not harder.
What is the USMLE Step 1?
The United States Medical Licensing Examination (USMLE) Step 1 is designed to ensure that medical students have a strong foundation in the basic sciences before moving on to clinical training. Here is something you should know about the USMLE Step 1:
- Focuses on subjects like anatomy, physiology, biochemistry, pathology, microbiology, pharmacology, and behavioral sciences.
- Assesses both factual knowledge and the ability to apply it in clinical scenarios.
- Passing Step 1 is essential for medical licensure in the U.S.
Are you also preparing for the USMLE Step 1? Then, you should definitely enroll in Academically’s USMLE Preparation course. You will get all the resources and guidance you need to pass the exam on the first attempt.
USMLE Step 1 Exam Format
| Feature | Details |
| Exam Type | Computer-based multiple-choice examination |
| Total Duration | Approximately 8 hours |
| Number of Blocks | ~7 blocks |
| Questions per Block | ~40 questions |
| Time per Block | 60 minutes |
| Total Questions | Approximately 280 |
| Break Time | 45 minutes total (can be used between blocks) |
| Question Style | Clinical vignettes with labs, imaging, and mechanisms |
| Tested Areas | Basic sciences + clinical application |
| Scoring | Pass/Fail (performance still reflects competence level) |
USMLE Step 1 Sample Questions & Explanations
Q. A 53-year-old man comes to the physician because of a dry scaly rash on his body for the past year. He has had a 15- kg (33-lb) weight loss during the past year. He is 178 cm (5 ft 10 in) tall and now weighs 54 kg (120 lb); BMI is 17 kg/m2. His stools have a large volume and float. Which of the following nutrient deficiencies is most likely?
(A) Magnesium
(B) Vitamin A
(C) Vitamin B12 (cobalamin)
(D) Vitamin C
(E) Zinc
Correct Answer: B) Vitamin A
Explanation:
- Bulky, floating stools indicate steatorrhea, suggesting fat malabsorption.
- Fat malabsorption leads to deficiencies in fat-soluble vitamins (A, D, E, K).
- Vitamin A deficiency causes dry, scaly skin (xerosis).
Q. Serum LDL-cholesterol concentrations are measured in blood samples collected from 25 healthy volunteers. The data follow a normal distribution. The mean and standard deviation for this group are 130 mg/dL and 25 mg/dL, respectively. The standard error of the mean is 5.0. With a 95% confidence level, the true mean for the population from which this sample was drawn falls within which of the following ranges (in mg/dL)?
(A) 105-155
(B) 120-140
(C) 125-135
(D) 128-132
(E) 129-131
Correct Answer: B) 120–140
Explanation:
- Formula: 95% CI = mean ± 1.96 × SEM
- Calculation: 130 ± (1.96 × 5) = 130 ± 9.8
- Range ≈ 120–140
Q. A 39-year-old man comes to the physician because of a 6-month history of progressive shortness of breath. He has had a cough productive of white sputum for 2 years. He smoked 1 pack of cigarettes daily for 16 years but quit 10 years ago. He is in mild respiratory distress with pursed lips and a barrel chest; he is using the accessory muscles of respiration. Breath sounds are distant and crackles are present in the lower lung fields bilaterally. Pulmonary function tests show a decreased FEV1:FVC ratio, increased residual volume, and decreased diffusion capacity. An x-ray of the chest shows hyperinflation and hypertranslucency of the lower lobes of both lungs. Which of the following is the most likely diagnosis?
(A) Asthma
(B) Bronchiectasis
(C) Chronic pulmonary fibrosis
(D) Cystic fibrosis
(E) Emphysema
Correct Answer: E) Emphysema
Explanation:
- Decreased FEV1/FVC = obstructive lung disease
- Decreased diffusion capacity and hyperinflation are classic for emphysema
- Lower lobe involvement suggests panacinar emphysema
Q. Investigators conduct a study that evaluates the effect of finasteride on the incidence of prostate cancer in 500 patients. The investigators recruit an additional 1000 patients for the study. Which of the following effects will this have on the research study?
(A) Greater chance of a Type I error
(B) Greater chance of a Type II error
(C) Less chance of a Type I error
(D) Less chance of a Type II error
(E) Impossible to predict
Correct Answer: D) Less chance of a Type II error
Explanation:
- Increasing sample size increases statistical power
- This reduces the chance of missing a true effect (Type II error)
Why Practicing Sample Questions Is Essential
Practicing USMLE Step 1 sample questions is one of the most effective ways to prepare because it helps you:
- Develop clinical reasoning skills
- Identify weak areas early
- Improve test-day stamina and pacing
- Recognize frequently tested concepts
- Learn how NBME-style questions are written
High-Yield Step 1 Study Tips
- Practice questions under timed conditions
- Always review why incorrect options are wrong
- Focus on pattern recognition, not memorization
- Track weak areas and revise strategically
- Use mnemonics and summary tables for revision
Final Thoughts
The USMLE Step 1 is challenging, but with the right approach, it is absolutely manageable. Practicing high-quality sample questions builds confidence, sharpens clinical reasoning, and prepares you for the real exam environment. Use questions actively, learn from mistakes, and focus on understanding, not memorizing.
Consistent practice is the key to Step 1 success. If you have any questions or need guidance, just reach out to the experts Academically. They will help you with everything you need.