Psychometric Properties of Intolerance of Uncertainty Scale (IUS-5) in a Sample of Nurses: A Methodological Study.

BACKGROUND AND

OBJECTIVE

The Intolerance of Uncertainty Scale (IUS-12) is widely used in both clinical and community studies. Due to the length and inconsistent factor structure of the IUS-12, an abbreviated version consisting of five items (IUS-5) has been proposed. However, no study has examined its psychometric properties aside from the preliminary work by its developers. The current study investigated the factor structure of the IUS-5 as well as its reliability and validity.

METHOD: A sample of 315 nurses completed an online self-report questionnaire during the COVID-19 pandemic.

RESULTS

Confirmatory factor analysis of the IUS-5 suggested a deletion of one item. The final analysis supported a one-factor solution on the remaining four items (IUS-4) with a McDonald's omega of 0.77. The validity of IUS-4 was assessed by testing its positive and negative correlations with existing related and contrary measures, respectively. Further, the validity of the IUS-4 was supported through known-group validation.

CONCLUSIONS

This is the first psychometric assessment of the IUS-5 measure of intolerance of uncertainty in a sample of nurses. Results from the current study supported a shorter measure of four items. However, more work needs to be conducted to examine the IUS-4 and IUS-5 in samples of healthcare providers with different cultural and linguistic backgrounds.