Abstract

Extant ACT process measures are typically circumscribed in their focus (limited to particular theoretical sub-processes or contexts of application) and have been subject to critique in terms of their discriminant validity and conflation of process and outcome variables. Conceptual questions therefore remain regarding how best to operationalize and measure core ACT processes. In this study, we describe the development of a new general measure of ACT processes (the CompACT) and explore the measure's factor structure, validity and reliability. In phase one, ACT experts rated the face and content validity of 106 items using a Delphi consensus methodology, and produced an initial 37-itemed measure. In phase two, a non-clinical sample of participants (N = 377) completed the CompACT and measures of other theoretically related and unrelated variables. An exploratory factor analysis suggested a theoretically-coherent three-factor structure (clustering ACT's six processes into three dyadic processes) for a 23-itemed version of the CompACT. The CompACT demonstrated good internal consistency, and converged and diverged in theory-consistent ways with other measured variables: higher levels of psychological inflexibility were associated with higher levels of distress and lower levels of health and wellbeing. The CompACT shows initial promise as a general measure of ACT processes.