Although uncertainty and ambiguity have been used interchangeably within the anxiety literature, no studies have directly compared the psychometric properties and predictive utility of two commonly used scales to assess these constructs, the Intolerance of Uncertainty Scale (IUS) and the Tolerance of Ambiguity Scale (TOA). Furthermore, previous findings of the individual scales have been inconsistent regarding their factor structure and potential clinical utility. Therefore, the current study aims to independently evaluate the factor structure of the IUS and TOA utilizing exploratory and confirmatory factor analysis. Additionally, predictive utility of the scales was evaluated with correlation and regression analyses. Data were collected across 3 studies. Results suggest two-factor solutions provide the best-fitting models for both scales; however, these findings differ from previous studies. The IUS and its subscales provide greater predictive utility for anxiety and related areas of psychopathology compared to the TOA, suggesting that the IUS and uncertainty may be more closely related to anxiety and related symptoms. Future studies should continue to examine the interconnected role of uncertainty and ambiguity within anxiety and other forms of psychopathology.

尽管不确定性和模糊性在焦虑文献中可以互换使用，但没有研究直接比较两种常用量表的心理测量特性和预测效用来评估这些结构，即不确定性不容忍量表（IUS）和模糊性容忍量表（TOA） ）。此外，先前对各个量表的研究结果在其因素结构和潜在的临床实用性方面不一致。因此，本研究旨在利用探索性和验证性因素分析独立评估 IUS 和 TOA 的因素结构。此外，还通过相关性和回归分析评估了量表的预测效用。数据是通过 3 项研究收集的。结果表明，双因素解决方案为两种量表提供了最佳拟合模型；然而，这些发现与之前的研究不同。与 TOA 相比，IUS 及其子量表对焦虑和精神病理学相关领域提供了更大的预测效用，这表明 IUS 和不确定性可能与焦虑和相关症状更密切相关。未来的研究应继续研究焦虑和其他形式的精神病理学中不确定性和模糊性的相互关联的作用。