Factor Structure, Validity and Reliability of the Intolerance of Uncertainty Scale-12 (IUS-12) in a Greek Undergraduate Sample

Intolerance of Uncertainty (IU) is described as the tendency to avoid uncertain states and exhibit negative responses to uncertain situations on cognitive, emotional, and behavioral levels. It is considered a transdiagnostic cognitive bias that plays a role in developing and maintaining psychopathology. The Intolerance of Uncertainty Scale-12 (IUS-12) has proven to be a sound measure of intolerance of uncertainty with excellent validity and reliability. Although research has supported a two-factor structure of IUS-12, most recent studies also suggest a bifactor model. The present study examines the factorial structure, validity, and reliability of the Greek version of IUS-12 with a sample of 959 university students (66.6% female) aged 19.63 years (SD = 3.20). Confirmatory Factor Analysis showed that although the two-factor solution adequately fit the data, the bifactor model better fit with IU total as an underlying one-factor. Internal consistency and validity were excellent for the total IUS-12 and Prospective and Inhibitory Anxiety subscales. Our findings support recent findings concerning the factorial structure of IUS-12 and the scale's psychometric qualities in a Greek undergraduate sample. We expect that future research with clinical samples will confirm the screening and clinical utility of IUS-12.