Intolerance of Uncertainty Scale – Short Form (IUS-12)
Author of Tool:
Carleton, Norton, & Asmundson
Freeston, M., Rhéaume, J., Letarte, H., Dugas, M. J., & Ladouceur, R. (1994). Why do people worry? Personality and Individual Differences, 17, 791-802. doi: 10.1016/0191-8869(94)90048-5Carleton, R. N. (in press). The intolerance of uncertainty construct in the context of anxiety disorders: Theoretical and practical perspectives. Expert Review of Neurotherapeutics.
Carleton, R. N., Mulvogue, M. K., Thibodeau, M. A., McCabe, R. E., Antony, M. M., & Asmundson, G. J. G. (2012). Increasingly certain about uncertainty: Intolerance of uncertainty across anxiety and depression. Journal of Anxiety Disorders, 26, 468-479.
Carleton, R. N., Norton, M. A., & Asmundson, G. J. G. (2007). Fearing the unknown: A short version of the intolerance of uncertainty scale. Journal of Anxiety Disorders, 21, 105-117. doi: S0887-6185(06)00051-X [pii]10.1016/j.janxdis.2006.03.014
Carleton, R. N., Gosselin, P., & Asmundson, G. J. G. (2010). The intolerance of uncertainty index: Replication and extension with an english sample. Psychological Assessment, 22, 396-406. doi: 10.1037/a0019230
Carleton, R. N., Weeks, J. W., Howell, A. N., Asmundson, G. J. G., Antony, M. M., & McCabe, R. E. (2012). Assessing the latent structure of the intolerance of uncertainty construct: An initial taxometric analysis. Journal of Anxiety Disorders, 26, 150-157.
Gosselin, P., Ladouceur, R., Evers, A., Laverdiere, A., Routhier, S., & Tremblay-Picard, M. (2008). Evaluation of intolerance of uncertainty: Development and validation of a new self-report measure. Journal of Anxiety Disorders, 22, 1427-1439. doi: 10.1016/j.janxdis.2008.02.005
Khawaja, N. G., & Yu, L., N. H. (2010). A comparison of the 27-item and 12-item intolerance of uncertainty scales. Clinical Psychologist, 14, 97-106. doi: 10.1080/13284207.2010.502542
McEvoy, P. M., & Mahoney, A. E. J. (2011). Achieving certainty about the structure of intolerance of uncertainty in a treatment-seeking sample with anxiety and depression. Journal of Anxiety Disorders, 25, 112-122. doi: 10.1016/j.janxdis.2010.08.010
Primary use / Purpose:
The IUS-12 is a short version of the original 27-item Intolerance of Uncertainty Scale (Freeston, Rhéaume, Letarte, Dugas, & Ladouceur, 1994) that measures responses to uncertainty, ambiguous situations, and the future (Carleton, in press). The 12 items are rated on a 5-point Likert scale ranging from 1 (not at all characteristic of me) to 5 (entirely characteristic of me).
The Intolerance of Uncertainty Scale – Short Form (IUS-12) has a strong correlation with the original scale, rs = .94 to .96 (Carleton, Norton, et al., 2007; Khawaja & Yu, 2010), a continuous latent structure (Carleton, Weeks et al., 2012), and has been shown to have two factors (Carleton, Norton, et al., 2007; McEvoy & Mahoney, 2011), prospective IU (7 items; e.g., “I can’t stand being taken by surprise”) and inhibitory IU (5 items; e.g., “When it’s time to act, uncertainty paralyses me”), both with identically high internal consistencies, α = .85 (Carleton, Norton, et al., 2007).
The IU construct has been found to be ubiquitous, with scores comparable across anxiety disorders and depression (Carleton, Mulvogue et al., 2012). The IUS-12 was selected to measure IU because it is comparable to, but briefer than, the longer original IUS (Khawaja & Yu, 2010) and the new symptom-focused Intolerance of Uncertainty Index (IUI; Carleton, Gosselin, & Asmundson, 2010; Gosselin et al., 2008).
Good convergent and discriminant validity, as well as internal consistency, have been demonstrated by the total score and both subscale scores (Carleton, Norton, et al., 2007; McEvoy & Mahoney, 2011).
Prospective Anxiety Subscale: sum of items 1,2,4,5,8,9,11
Inhibitory Anxiety Subscale: sum of items 3,6,7,10,12
Total Score: sum of all items
For sample means see Carleton et al., 2012 and/or McEvoy & Mahoney, 2011 (reference above).