The key components of a clinical psychology formulation: A consensus study

Psychological formulation is a key competency for clinical psychologists. However, there is a lack of consensus regarding the key components and processes of formulation that are hypothesized to contribute to poor reliability of formulations. The aim of this study was to develop consensus on the essential components of a formulation to inform training for clinical psychologists and best practice guidelines.

A Delphi methodology was used. Items were generated from the literature and discussed and refined with a panel of experts (n = 10). In round one, 110 clinical psychologists in the United Kingdom rated the importance of components of formulation via an online questionnaire. Criteria for consensus were applied and statements were rerated in round two if consensus was not achieved.

Consensus was achieved on 30 items, with 18 statements regarding components of a formulation and 12 statements regarding formulation process. Items that clinicians agreed upon emphasized the importance of integrating sociocultural, biological, strengths and personal meaning alongside well-established theoretical frameworks. Consensus was not reached on 20 items, including whether a formulation should be parsimonious or adhere to a model.

Our findings provide mixed evidence regarding consensus on the key components of formulation. There was an agreement that formulation should be client-led and incorporate strengths and sociocultural factors. Further research should explore client perspectives on the key components of formulation and how these compare to the clinicians' perspectives.