1 Boring Old Man

What Is the “Bible of Psychiatry” Supposed to Do?
The Peculiar Challenges of an Uncertain Science
Discover Magazine
by Vaughn Bell
May 22nd, 2012

The American Psychiatric Association have just published the latest update of the draft DSM-5 psychiatric diagnosis manual, which is due to be completed in 2013. The changes have provoked much comment, criticism, and heated debate, and many have used the opportunity to attack psychiatric diagnosis and the perceived failure to find “biological tests” to replace descriptions of mental phenomena. But to understand the strengths and weaknesses of psychiatric diagnosis, it’s important to know where the challenges lie.

Think of classifying mental illness like classifying literature. For the purposes of research and for the purposes of helping people with their reading, I want to be able to say whether a book falls within a certain genre—perhaps supernatural horror, romantic fiction, or historical biography. The problem is similar because both mental disorder and literature are largely defined at the level of meaning, which inevitably involves our subjective perceptions. For example, there is no objective way of defining whether a book is a love story or whether a person has a low mood. This fact is used by some to suggest that the diagnosis of mental illness is just “made up” or “purely subjective,” but this is clearly rubbish. Although the experience is partly subjective, we can often agree on classifications…

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Notice that I’ve not discussed mental illnesses as if they were genuinely distinct pathologies that we are trying to “discover.” This is because these cases are the minority in medicine [largely infections or discrete genetic disorders] and the majority of illnesses of any type are not like this. For example, cancer, heart disease, stroke, emphysema and the majority of non-infectious diseases involve at least some arbitrary cut-off points. Good diagnoses are human creations that help us better capture a group of related symptoms that respond to a similar treatment plan. They are tools, by and large—not inherent truths…

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On top of the unsteady foundations of diagnosis are pressures from drug companies (who want diagnoses to sell treatments for, rather than the other way round), insurance companies [who want to change or discard diagnoses because they are costing them too much money], professional organisations [who want to widen the range of problems they can charge for], and researchers [who want to make their name championing a specific disorder]. So with all this in mind, you can see why the DSM is so contentious and, some would say, a mess. The irony is that when the DSM-5 comes out, not a lot will change. Most professionals will still use the same handful of core diagnoses and 90% of the manual will be ignored.

It’s also ironic that modern psychiatry has become fixated on classification. The idea is that better classification will lead to better treatment but the majority of treatments are not diagnosis specific and never have been. That’s not to say that diagnosis isn’t a useful tool, but it’s important to make sure that we don’t confuse our tools with actual solutions. If we genuinely want to improve treatment for mental illness, it’s the solutions that matter.