Creating a compendium of third wave therapy strategies : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Psychology at Massey University, Palmerston North, New Zealand

Abstract

Third Wave Cognitive Behavioural therapies have received much attention in the practice community recently. However, little has been done to understand how these therapies relate and diverge. Despite the varying theoretical models contributing to the Third Wave movement and their supposed varying therapeutic elements, studies have suggested that outcomes do not differ across these therapeutic approaches. This finding leaves room for the notion that shared or ‘common’ factors may be operating across these approaches. Exploration into common elements between these approaches is useful for identifying areas of overlap or uniqueness, shared processes of change, and perhaps components that may be particularly efficacious. Goldfried argued the best way to identify the commonalities among diverse therapeutic approaches is to compare them by their principles of change, or change processes (Goldfried, 1980). Research has investigated change processes for many approaches, including those of the Behaviour and Cognitive tradition. However, such extensive investigations have not been applied to the Third Wave approaches. Further, a lack of quality comparisons across these approaches, even at the more specific level of therapeutic strategies, represents a gap in the field. The present research first identified a set of strategies (84 items) within three Third Wave approaches: Dialectical Behaviour Therapy, Acceptance and Commitment Therapy and Mindfulness Based Cognitive Therapy. Strategies are sorted according to similarity in a card-sorting task, by two participant samples, a non-therapist sample (N=32) and a therapist sample (N=35). Sorting data were analysed using multidimensional scaling (MDS) to produce three three-dimensional models, representing each sample and a combined sample. The therapist sample was judged to represent the underlying relationships between strategies best. Three dimensions were identified that classified strategies according to their internal or external orientation; response to experience (accepting or exploratory in nature); and the perspectives involved (clients or external such as therapists). Additionally, 17 clusters were identified that comprised strategies perceived to represent similar concepts, five of which contained strategies from all three paradigms (Mindfulness; Noticing; Distress Tolerance and Acceptance; Therapist Style; and Observing and Perspective Taking). Commonalities and differences observed across the approaches are discussed and suggestions made for future validation of this model. Applications are discussed around informing investigations of change processes in the Third Wave and the integration of Third Wave therapy elements. This research presents opportunities for mapping strategies to various characteristics of the client, therapist or disorder, for example, and then identifying effective strategy use among these variables