Welcome to Module 3

As a PMHNP student, one of your most important skills is developing diagnostic reasoning. You’ll often be the first to sort through overlapping symptoms, medical mimics, and patient narratives to clarify what’s really going on. This module will introduce you to the framework of the DSM-5-TR, common psychiatric categories, and how to think critically about differential diagnoses.

By the end of this lesson, you will be able to:

• Understand the structure and use of the DSM-5-TR.

• Differentiate between major psychiatric categories.

• Apply a systematic approach to building a differential diagnosis.

• Recognize red flags that require urgent action.