The USMLE* Step 1 is the first in the series of three USMLE exams that candidates must pass in order to qualify for medical licensure in the United States. It is a one-day computer exam taken by most medical students at the end of their second year of medical school. It is also taken by thousands of international medical graduates (IMGs) who wish to practice medicine in the United States.

Unlike previous USMLE exams in which candidates all took the same test on the same dates, the computer versions are administered by appointment on a year-round basis.

The Step 1 emphasizes basic science principles, specifically in anatomy, behavioral science, biochemistry, microbiology, pathology, pharmacology, and physiology. Interdisciplinary areas such as genetics, immunology, and nutrition are also tested.

The Step 1 exam contains 350 questions and spans 8 hours of testing (including an hour of break time). It is administered as 7 one-hour "blocks" of 50 questions each. You will be able to skip back and forth among test questions, but only within a particular block. Once you leave a block (or time expires for that block), you will not be able to return to the questions of that block.

Step 1 questions are NOT grouped by subject within a block. For example, you won't find a section devoted to biochemistry. This random ordering of items presents you with a unique challenge. You must switch from thinking about one subject, such as pathology, to another, such as behavioral science, without skipping a beat.

In total, you will have 45-60 minutes of "break" time depending on whether you choose to complete the 15 minute tutorial at the start. You can "add" to your break time by finishing a block early. Please note, however, that finishing blocks early does not add to your total "test time" which remains constant at 7 hours. That means that you can't add time to one block by finishing another block ahead of time. You should only take breaks BETWEEN blocks; leaving the testing area DURING a block will be noted as a testing irregularity.

Question Formats
The only question format currently on the USMLE Step 1 is one best answer (matching questions as well as negatively phrased questions were eliminated a few years ago). Some of the Step 1 items test your fund of knowledge directly; however, the majority require application of basic science principles to clinically-relevant situations. You will also be asked to identify microscopic and gross specimens, interpret graphic or tabular information, and solve simple clinical problems.

In an effort to make the Step 1 exam more medically relevant, the USMLE items often assess basic medical science concepts in a clinical context. While some points are asked in a fairly traditional, straightforward manner, you will also be presented with many clinical vignettes. This style typically involves fairly long lead-in scenarios followed by relatively brief response options.