Validating a Short Version of the Intolerance of Uncertainty Scale-12 (IUS-12)

Abstract

Background: This study aims to validate the short version of the Intolerance of Uncertainty Scale-12 (IUS-12).Methods: A comprehensive set of questionnaires, including the IUS-12, STAI-T, PSWQ, CES-D, and K-CSI, was administered and completed by 404 participants. The average age of the participants was 31.29 years (SD=9.18), comprising 114 men, 287 women, and 3 individuals identifying with the other gender. We conducted a factor analysis on the collected data and compared the fit indices of one-factor, two-factor, and bifactor models. Furthermore, a multiple-group confirmatory factor analysis evaluated measurement invariance between the men’s and women’s groups. Correlational analyses were also conducted.Results: Data from the study show that the bifactor model was the most appropriate, demonstrating good internal consistency. The Omega coefficients and explained common variance were computed to evaluate the dimensionality of the IUS-12, validating the use of the total score of the scale. Its factor model also showed that the measurement invariance sustained between two gender groups. The correlation analyses between the IUS-12 and other scales assessing attributes such as trait anxiety, worry, depression, and avoidance coping strategy supported convergent validity.Conclusions: These findings suggest that the IUS-12 is a reliable and valid measure for assessing the intolerance of uncertainty. The study also discusses its limitations and offers recommendations for future research endeavors.