Book Preface

The USMLE^© Step 3 is the last in a series of 3 USMLE examinations that all physicians applying for a license to practice medicine in the United States are required to pass. After successfully completing the 3 steps of the USMLE, a physician is eligible to practice medicine in an independent, unsupervised setting (some period of U.S. postgraduate training is also required).

This test is not merely a more advanced and detailed version of the Step 2 CK or CS exams. Understanding this concept is key to this challenging exam. Step 3 tests whether a physician not only can assimilate data and diagnose clinical conditions but also has acquired the ability to make clinical decisions about patient management in a way that ensures appropriate management in an unsupervised setting. In addition, Step 3 will test your understanding of basic science correlations.

How can the Step 3 test all first-year interns if they are working in such varied subspecialty settings? The same concepts that medicine house-officers learn about managing a diabetic with heart failure can be equally applied to the postsurgical patient with heart failure.

How Is Step 3 Different?

Unlike the Step 2 exams, which emphasize diagnosis of medical conditions, Step 3 evaluates your ability to evaluate the severity of a patient’s condition and discern the most appropriate clinical management based on the presenting scenario. This assessment of your clinical judgment distinguishes Step 3 from Step 2. In Step 3, you are required to think beyond the diagnosis (which is often implicit in the question itself) and make decisions in management. The cases presented will include options that may all appear appropriate; however, for the presented situation, there is only ever one correct answer. Your interpretation of laboratory data, imaging, and elements of the presenting history and physical examination will assist you in selecting the correct management.

Clinical Encounter Frames

Multiple-choice and case-simulation questions are presented in one of three clinical encounter frames: initial care, continuing care, and urgent care. The encounter frame determines the amount of history, as well as clinical and laboratory test results, that are available to you. More importantly, the encounter frame influences how you’ll proceed with management. For example, a longstanding patient with a history of repeated hospitalizations for asthma who presents with shortness of breath would be approached differently than if she were presenting for the first time to a clinic complaining of periodic dyspnea or if she presented to the emergency department with an acute asthma attack. The majority of test items (50 to 60 percent) in Step 3 involve the management of continuing-care patients. In the continuing-care setting, you are tested on your ability to recognize new problems in an existing condition, assess severity, establish prognosis, monitor therapy, and perform long-term management.