Begin by mastering the following mnemonic for the seven major adult diagnostic categories in the DSM-IV-TR:

Notice that these categories deviate somewhat from DSM-IV-TR dogma. For example, I call ADHD a “cognitive disorder,” whereas the DSM-IV-TR classifies it as a “disorder of infancy, childhood, and adolescence.” Also, I classify eating disorders under somatoform disorders, whereas the DSM-IV-TR puts them in a separate chapter. My purpose here is not to create a new classification of psychiatric disorders but simply to rearrange them into seven categories for ease of memorization.

Now that you’ve memorized the major disorders, you need to memorize the diagnostic criteria. Begin by disregarding the voluminous exclusions and modifiers listed by the DSM-IV-TR and instead focus on the actual behaviors and affects needed to make the diagnosis.

For example, under schizophrenia in the DSM-IV-TR are six categories of criteria, labeled A through F. B is the usual proviso that the disorder must cause significant dysfunction, which is true for all the disorders, so you don’t need to memorize it. D tells you to rule out schizoaffective and mood disorder before you diagnose schizophrenia— another obvious piece of information; don’t use up valuable neurons memorizing it. E reminds you to rule out substance abuse or a medical condition, which you should do before making any diagnosis, and F deals with the arcane issue of diagnosing schizophrenia in someone who’s autistic. So, only two essential criteria are left: A (symptoms) and C (duration).

This section lists mnemonics for most of the major disorders, but it does not cover how to ascertain the diagnoses, which involves the skillful use of probing questions and specific follow-up questions. These are covered in detail in Chapters 23,24,25,26,27,28,29,30,31, where the full DSM-IV-TR criteria are spelled out.