Science Versus Pragmatism in the DSM: Finding A Middle Ground

Nassir Ghaemi’s “Couch Pragmatism,” published in the October issue of Psychiatric Times, is the latest entry in an ongoing debate with Allen Frances in the blogosphere of Psychiatric Times and Psychology Today over the DSM and the DSM-5 process. As a colleague and friend of both the disputants in this controversy, I find the squabble regrettable and unnecessary. That said, I present here what I see as a middle ground that frames the meaning and role of pragmatism as a bridge to serve both science and clinical practice.

I begin with a note on the use of the term “pragmatism,” which has become a rather chameleon word. In one of his early, founding statements of pragmatism as a philosophical movement, CS Peirce wrote: “Consider what effects, which might conceivably have practical bearings, we conceive the object of our conception to have. Then, our conception of those effects is the whole of our conception of the object.”^{(1, p 31)} This statement suggests a double sense of pragmatism: first, as finding the meaning or truth value of a conception in its practical consequences, and second (the sense that Peirce would develop further), as involving a concordance of pragmatism with the scientific method of verification through experiment. Popular usage has tended toward the first sense, with the result that “pragmatic” has become almost synonymous with “practical.” Frances has adopted this first usage, and I will do the same in this article.

Is there a conflict between science and pragmatism in the DSM?
In my opinion there is not. The DSM does and must involve both. The DSM must use the science that is available, but it must also make countless judgment calls that are not grounded in solid empirical evidence—and surely it makes sense to consider practical consequences in doing the latter. Examples of non-empirically based decisions are not hard to come by. First, there is the question as to whether a condition should be listed at all in the DSM as a disorder. Various groups of “paraphilics,” for instance, have protested as did homosexuals decades ago, challenging the pathologic status of their sexual difference. To invoke a provocative example, what is the empirical evidence that pedophilia is a psychiatric disorder, rather than simply a socially repellant behavior? A similar question, raised and studied by John Sadler, involves the bad-conduct disorders such as Conduct Disorder and Antisocial Personality Disorder.²

Second, once a disorder is admitted into the DSM, we make countless non-empirically based decisions about the structure of the diagnostic criteria—what they are, how many there are, how many are needed to declare the diagnosis, etc. All such decisions utilize the available empirical evidence, but they are hardly dictated by that evidence. And where judgment comes in, so does consideration of consequences. A ready example is the criteria set for a major depressive episode. The requirement of only 2 weeks of symptoms, and only 5 of 9 of the criteria, may cast too wide a net and bring in too many false positives.

Then there are the much disputed sub-threshold conditions, with most of the attention going to Psychosis Risk Syndrome, now renamed Attenuated Psychotic Symptoms Syndrome (APSS). In the absence of a clear marker identifying someone as pre-schizophrenic, how can we avoid non-empirically based, risk-benefit decisions over whether to declare APSS a DSM disorder? Even if we had good data on the ratio of false positive to false negative outcomes from using this diagnosis, we would still have to make a non-empirical judgment about the tolerable rate of false positives.

Finally, let me mention the place of dimensions in DSM-5—both the disorder-related scales and the crosscutting measures. This discussion of dimensions versus categories is a good example of abundant evidence and abundant opinion. The one thing we can expect is that the decisions made by the task force will be based on a complicated mix of empirical evidence and non-empirically based judgments.

For purposes of this discussion I will skip the bipolar/hypomania debate and assume that Ghaemi’s analysis is correct, as I don’t think it affects the larger discussion. Or it does so only if you assume that Frances is intentionally “gerrymandering” that diagnosis to support his conservative bias.

It does appear that Ghaemi is making that argument by writing about Frances’ caution in the use of neuroleptics: “The problem is simple and serious: this is psychiatric gerrymandering. . .But this gerrymandering based on which drugs we like or don’t like is no way to develop a diagnostic system...”³ In contrasting progress in internal medicine with lack of progress in psychiatry over the past century, Ghaemi writes that “Because of the ‘pragmatic’ approach, we have been doomed, for an entire generation, to failure in biological and treatment studies.” The usual explanation for our failures in psychiatric research is that mental diseases involve the brain and are harder to understand than other medical conditions. I doubt that Ghaemi would want to argue that, say, in schizophrenia research, our failures over the past decades to produce more understanding are because of the researchers’ being driven by pragmatic rather than scientific interests.

So what does this all come down to?
Both Dr Ghaemi and Dr Frances agree that in constructing a psychiatric nosology, clear scientific findings will always trump other considerations. Both also agree that the nosology will involve non-empirically based decisions and that these should include consideration of the practical effects of the respective decisions. And both express concern and skepticism over who will make these decisions.

So what is the fight about? We have one disputant who argues that we don’t sufficiently use the empirical evidence available in constructing our nosology, and another disputant who argues that the available evidence is often inadequate to dictate our decisions, forcing us to make non-empirically based decisions that include consideration of practical consequences. (And of course, the debate involves non-empirically based decisions as to whether, in any particular situation, there is or is not enough empirical evidence to close the discussion.)

Each side has a point in this debate. Since the construction of a nosology will always involve a balance of science and pragmatism, I would like to think that we could work on this in a spirit of collaboration rather than rancor—and I remain puzzled by the latter.

References
1. Peirce CS. How to make our ideas clear. In: Buchler J, ed. Philosophical Writings of Peirce. New York: Dover Press; 1955:23-41.
2. Sadler J. Values in Psychiatric Diagnosis. Oxford: Oxford University Press; 2005. See also: Sadler J. Vice Squad. Psychiatric Times. August 26, 2010. http://www.psychiatrictimes.com/blog/dsm-5/content/article/10168/1649840. Accessed November 17, 2010.
3. Ghaemi N. Couch Pragmatism. Psychiatric Times. 2010;27(10):16-21. http://www.psychiatrictimes.com/mood-disorders/content/article/10168/1642824. Accessed November 17, 2010.