Measuring Intolerance of Uncertainty after Acquired Brain Injury: Factor Structure, Reliability, and Validity of the Intolerance of Uncertainty Scale-12 (preprint)

ABSTRACT

Intolerance of uncertainty (IU) is a risk factor for poor mental health. Acquired brain injury (ABI; e.g., stroke, traumatic brain injury), often brings considerable uncertainty and increased mood disorder vulnerability. The Intolerance of Uncertainty Scale-12 (IUS-12) is a brief, well-validated measure of IU argued to comprise two subscales, Prospective Anxiety and Inhibitory Anxiety. Here, for the first time, we investigated its reliability and validity (N = 118), and factor structure (N = 176), in ABI. Both subscales had high test-retest reliability (ICCs of 0.75 and 0.86) and were significantly associated with mood disorder symptoms. The two-factor model was superior to a one-factor IU model fit. IUS-12 scores were stable despite great uncertainties of COVID-19, consistent with its conceptualisation as a trait. Consistent with recent debates about the factor structure of IUS-12 and, in exploratory analyses, we found indications of improved fits that warrant further investigation in independent ABI samples.