In a previous post, Rachel Cooper talked about the potential advantages of the ambiguity offered by the DSM-5 definition of mental disorder. I very much agree that the stipulation of necessary and sufficient conditions is unlikely to succeed in mapping such complex messy and controversial phenomena as “mental disorders”. However, I am unsure whether in this particular case an ambiguous definition is quite so benign as Rachel implies. It is true that few clinicians will pay attention to the introductory text, being more concerned with the features of the diagnosis they are dealing with at any particular moment, but this is not to say that the definition provided is not an important and influential part of the manual.
As a colleague Rachel Bingham and I suggested in a recent paper, a significant driver for attempting to define mental disorder emerged in the scientific and political fallout of the declassification of homosexuality from the DSM in 1973. The move to declassify came about through civil rights activism that highlighted, among other things, the lack of scientifically credible evidence to support the claim that homosexuality was a mental disorder: psychodynamically-driven theories assuming the pathological status of homosexuality were undermined once the existence of happy, functioning, well-adjusted gay individuals was acknowledged. Against this backdrop, it is understandable why the effort to seek out a clear cut definition of mental disorder, and thus clarify the domain of psychiatry, was so important. If psychiatry was to avoid being used as a tool of social control to pathologise behaviours simply seen as abnormal by society, it had better be able to delineate what counts as a mental disorder from what doesn’t.
Fast forward to today, and the DSM-5 definition attempts to bridge the ‘values-out’ versus ‘values-in’ camps with a broad definition subject to wide interpretation. This has its uses when the jury is still out, certainly, but we ought to be alert to the potential dangers of ambiguity in the wording of any working definition that is supported by the influential DSM. This is particularly so given concerns over the inflation of psychiatric categories and the perceived risks of pathologising what are essentially normal human behaviours. Only last month the diagnosis of Attention Deficit Hyperactivity Disorder was called into question by a leader in the field, and there has long been controversy over whether the DSM-5 criteria count the experience of bereavement as “major depression.” Sensible discretion in the application of the definition may be urged (akin to Rachel’s example from HLA Hart), but there are many competing interests at stake in diagnostic classification that may not in practice reflect the deliberations of a objective, dispassionate and sensible judge.
If one of the reasons for seeking a definition of mental disorder in the first place was to prevent psychiatry from over-reaching its boundaries, I’d argue that it could be better not to attempt to define the overarching category of “mental disorder” at all. This would be preferable to providing a scientific gloss to ambiguous terms that could potentially encompass far more behaviours, conditions and experiences than the authors of the definition ever intended.