Self-Assessment
Intolerance of Uncertainty Scale
Assess how uncertainty, ambiguity, and unpredictable situations affect your daily life.
The Research Behind the Scale
Definition
"the predisposition to react negatively to an uncertain event or situation"
Ladouceur et al. (2000), quoted in Hale et al. (2016). Resolving Uncertainty About the Intolerance of Uncertainty Scale-12. Journal of Personality Assessment.
Intolerance of uncertainty (IU) is a trait-like tendency. It describes how much uncertainty bothers you, not whether you experience it. Everyone faces uncertainty daily. The difference is in how much distress it creates.
Researchers first identified this pattern while studying people with generalized anxiety disorder (GAD) in the 1990s. Later work showed IU appears across many conditions. It is now considered a transdiagnostic factor, meaning it shows up in anxiety, depression, OCD, and other difficulties.
Scale History
Average IUS-12 Scores Across Groups
From Carleton et al. (2012), multiple samples
Score range: 12 to 60. Higher scores = more distress around uncertainty.
IU and Different Conditions
Meta-analytic correlations from Gentes & Ruscio (2011)
IU is not specific to one condition. It appears across anxiety, depression, and OCD. Researchers call this a "transdiagnostic" factor.
From the Research
"The original IUS consisted of 27 items developed from the clinical observation of people suffering from GAD."
Bottesi et al. (2019). Seeking certainty about Intolerance of Uncertainty. PLOS ONE.
Total score is the primary measure. We sum all your item responses (each rated 1 to 5). For the IUS-12, scores range from 12 to 60. For the IUS-27, scores range from 27 to 135.
We compare your IUS-12 score to published community sample data from Carleton et al. (2012): a community sample of 571 adults (mean = 29.53, SD = 10.96). This comparison shows where your responses fall relative to a research sample. It is not a clinical cutoff.
Why Total Score
"we ... recommend avoiding scoring the subscales altogether."
Hale et al. (2016). Resolving Uncertainty About the Intolerance of Uncertainty Scale-12. Journal of Personality Assessment.
Research using bifactor analysis has found that a single general IU factor best explains how people respond to these items. While two subscales (Prospective IU and Inhibitory IU) can be computed, they add limited unique information beyond the total. We show subscale scores as optional detail only.
Item source: Items used in this assessment come from the Intolerance of Uncertainty Scale protocol documented in the PhenX Toolkit, which states: "This protocol is freely available; permission not required for use."
| Metric | Value | Source |
|---|---|---|
| Internal consistency | α = .91 – .93 | Hale et al. (2016) |
| Test-retest reliability | r = .77 | Multiple studies |
| Community mean (IUS-12) | 29.53 (SD 10.96) | Carleton et al. (2012) |
| Undergraduate mean (IUS-12) | 27.52 (SD 9.28) | Carleton et al. (2012) |
About This Assessment
This tool presents items from the Intolerance of Uncertainty Scale as documented in the PhenX Toolkit protocol. The PhenX protocol states this instrument is freely available and permission is not required for use.
Items follow the PhenX protocol (source: PhenX Toolkit, citing Buhr & Dugas, 2002). The IUS-12 short form was developed by Carleton, Norton & Asmundson (2007). Reference data is from Carleton et al. (2012). Scoring guidance follows Hale et al. (2016).
This is a self-reflection and educational tool. It does not diagnose any condition, including generalized anxiety disorder, OCD, or depression. Reference bands are comparisons to one published community sample and are not clinical thresholds.
If uncertainty is causing significant distress or interfering with your daily life, please consult a mental health professional. For crisis situations, contact your local emergency services or a crisis helpline.