ABSTRACT
Descriptions and explanations of eating disorders have changed considerably over time, and according to the authorities who have written about them; and it is fairly safe to say they will do so again. However, within the current DSM (version IV) system of classification, eating-related disorders subsume three separate diagnoses. Each has distinct clinical features; at the same time they have many characteristics in common. Although diagnostic categories have certain merits for research and treatment, they are nevertheless rather arbitrary, and sometimes obscure the heterogeneity of the disease in terms of predisposing or causal factors. An alternative approach has taken a dimensional perspective on the eating disorders; the premise being that differences between a preoccupation with weight and diet, and the clinical form of the disorder, are essentially quantitative, and that the behavioural and psychological characteristics vary more in degree than in kind. In other words, the full-blown syndrome is viewed as the end-point along a continuum that begins with normal dieting, advances to excessive concern about weight, the emergence of some clinical symptoms, and finally a severe and pathological illness (Fairburn & Beglin, 1990; Kendler et al., 1991). In recent years, this viewpoint has become more prevalent – even in mainstream psychiatry – so that most would now agree that the eating disorders are more appropriately regarded as a ‘spectrum of pathology’ than as discrete disease entities. And so, although we continue to employ the DSM-IV diagnostic criteria and terminology for convenience, in practice our assessment of symptomatology typically reflects the dimensional view, and patients with milder forms of the disorders are treated alongside those with a more severe illness.
