Experimental manipulation of intolerance of uncertainty: a study of a theoretical model of worry

Intolerance of uncertainty has been identified as an important variable rel ated to worry and Generalized Anxiety Disorder (GAD) [Dugas, M. J., Gagnon, F., Ladouceur, R., & Freeston, M. H. (1998). Generalized anxiety disorder: a preliminary test of a conceptual model. Behaviour Research and Therapy, 36, 215-226; Ladouceur, R., Dugas, M. J,, Freeston, M. H., Rheaume, J., Bla is, F., Boisvert, J.-M., Gagnon, F., Br Thibodeau, N. (1999). Specificity o f Generalized Anxiety Disorder symptoms and processes. Behaviour Therapy, 3 0, 197-207]. The goal of the present study was to clarify the relationship between this cognitive process and worry by experimentally manipulating int olerance of uncertainty. A gambling procedure was used to increase intolera nce of uncertainty in one group (N = 21) and to decrease intolerance of unc ertainty in another group (N = 21). The results indicate that participants whose level of intolerance of uncertainty was increased showed a higher lev el of worry, compared to participants whose level of intolerance of uncerta inty was decreased. These results provide some initial clarifications as to the causal nature of the link between intolerance of uncertainty and worry . These results are coherent with our theoretical model of worry and GAD (D ugas et al., 1998), which stipulates that intolerance of uncertainty plays a key role in the acquisition and maintenance of excessive worry. (C) 2000 Elsevier Science Ltd. All rights reserved.