Introduction

One of the principal aims of a psychological assessment is to evaluate the form and function of target behaviours. The term case formulation can be defined as the process of operationalizing target behaviours1 (determining the form) and evaluating relationships among target behaviours and potential controlling factors (determining the function) for an individual client.

The aforementioned definition has several important features. First, the identification of causal functional relationships is a central element of case formulation. Although functional relationships may be either correlational or causal, by itself, a functional relationship implies only covariation [Page 165]between two variables. Because a case formulation is primarily used in treatment planning, the identification and quantification of causal functional relationships among target behaviours and controlling factors are of primary interest.

Causal functional relationships are ...