Abstract
Overall, the evidence supports both the CB and the IPT theoretical models of EDs in terms of BN, although the evidence for these as models of AN is more patchy. At present the evidence base for CB models is better than that for the IPT model, but this can be explained by the fact that IPT is a relatively recent development in terms of treatments for EDs. Since both models are primarily models of maintenance, it is possible AN and BN are maintained by factors as described in both CB and IPT models. While CB models focus on attitudes to weight and shape and behavioural symptoms and IPT models focus on interpersonal difficulties, the long-term outcomes of treatments using the models is similar. It is thus postulated that CBT works by improving eating habits and attitudes, which leads to improved interpersonal functioning, whereas IPT works by improving interpersonal functioning, which leads to improvements in eating habits and attitudes (Fairbum, 1993). However, although the models are postulated to work in opposite ways, the suggested treatment structure is similar for both, relying on approximately nineteen outpatient sessions over eighteen to twenty weeks. ' However, to fully evaluate these models, and thus to be able to effectively compare and contrast them, more research needs to be done, particularly in terms of IPT treatment and model elements in general and for CB model elements and treatment for AN.