Evaluation of intolerance of uncertainty: development and validation of a new self-report measure.

Intolerance of uncertainty represents an important risk factor for development of anxiety disorders. However, few measures have been developed in order to evaluate this construct. Four studies were conducted in order to validate a new instrument evaluating intolerance of uncertainty: the Intolerance of Uncertainty Inventory (IUI). The first study described the questionnaire's development and evaluated the psychometric properties of its preliminary version. Study 2 examined the reliability and the factorial validity of the final version of the questionnaire, while Study 3 mainly addressed its convergent validity. Finally, Study 4 examined the questionnaire's temporal stability. Factorial analyses confirmed the IUI's validity. Results also supported the IUI's reliability, convergent validity, and temporal stability. The IUI is the first instrument that offers the possibility of measuring intolerance of uncertainty as a tendency to consider uncertainties to be unacceptable, as well as in terms of cognitive and behavioral manifestations.