Intolerance of Uncertainty (IU) model developed by M.H.Freeston, R.Ladouceur, M.J.Dugas, and others. The IU model is developed to explain worry and generalized anxiety disorder (GAD). Ladouceur, Talbot, and Dugas (1997) define IU as “…the way an individual perceives information in ambiguous situations and responds to this information with a set of cognitive, emotional, and behavioral reactions” (p. 356). Mentioned reactions are negative and independent of the possibility of the actual occurrence of the situation and the associated effects (Ladouceur, Gosselin, & Dugas, 2000). IU has also been defined as “a dispositional characteristic that results from a set of negative beliefs about uncertainty and its implications and involves the tendency to react negatively on an emotional, cognitive, and behavioral level to uncertain situations and events” (Buhr & Dugas, 2009, p. 216). Another research suggests that IU is a cognitive feature of anxiety, worry, and mood disorders (Reuman et al., 2015). Moreover, emerging evidence indicates that IU may be a shared element of all emotional disorders (Boswell et al., 2013).  However, there are few research-based discussions whether IU is a trait-like concept or a state.

The concept of IU is assessed by the IU Scale (IUS; Freeston et al., 1994), which measures “emotional, cognitive and behavioral reactions to ambiguous situations, implications of being uncertain, and attempts to control the future” (Freeston et al., 1994, p. 791).

And here are some of the most recent papers/studies on Intolerance of Uncertainty (more in PubMed):

Intolerance of Uncertainty