CBT for GAD: Impact of Cognitive Processing on Treatment Outcome

Generalized anxiety disorder (GAD) is a condition characterized by chronic and excessive worry and anxiety. Over the past 15 years, the investigators have developed a cognitive-behavioural treatment that leads to the remission of GAD in approximately 60% to 75% of affected individuals. Although these numbers are encouraging, there remain a considerable proportion of patients who do not fully benefit from treatment. With the goal of improving treatment efficacy, the investigators have recently carried out a series of related studies on the way individuals with GAD and high worriers process uncertain or ambiguous information from their environment. The findings show that these individuals display biases in attention for, and appraisal of, uncertain or ambiguous information. Specifically, individuals with GAD and high worriers preferentially allocate their attention to uncertainty-related stimuli and appraise ambiguous information in a threatening manner. In this study, the investigators examine the impact of these information processing biases, measured at intake, on the efficacy of cognitive-behavioural treatment for GAD. The investigators also examine the impact of residual information processing biases, measured at posttreatment, on the maintenance of treatment gains over 18 months following treatment. The main hypotheses are (1) that high levels of pretreatment biases will predict poorer outcomes immediately following therapy, and (2) that high levels of posttreatment biases will predict relapse during the 18 months following therapy. If, as expected, information processing biases predict poor short- and long-term treatment outcomes for individuals with GAD, the investigators will expand the treatment to integrate strategies that directly target these biases in order to increase its efficacy.