Psychometric properties of the Iranian version of the Anxiety Sensitivity Index-3 (ASI-3).

Introduction: Anxiety sensitivity plays a prominent role in the etiology of anxiety disorders. This construct has attracted widespread interest from experts and researchers. The Anxiety Sensitivity Index (ASI-3) is the most common scale for measuring anxiety sensitivity.

Objective: To analyze the psychometric properties and factor structure of the ASI-3 in Iranian student samples.

Methods: 220 students (135 women, 85 men) from Kermanshah University of Medical Sciences were selected by the convenience sampling method to evaluate the psychometric properties and analyze the factor structure of the ASI-3. The subjects were also asked to complete the Acceptance and Action Questionnaire-II (AAQ-II), Whiteley Index, Intolerance of Uncertainty, and Neuroticism scales. LISREL and SPSS were used to analyze the data. Cronbach's alpha and correlation coefficients were calculated and confirmatory factor analysis was conducted.

Results: The results of the confirmatory factor analysis revealed a three-factor structure with physical, cognitive, and social components (comparative fit index = 0.94; normed fit index = 0.91; root mean square error of approximation = 0.09). The ASI-3 had positive and significant correlations with health anxiety (0.59), intolerance of uncertainty (0.29), and neuroticism (0.51). Furthermore, the ASI-3 had a negative and significant correlation with the AAQII (-0.58). Cronbach's alpha coefficients for the whole scale and for the physical, cognitive, and social concerns factors were 0.90, 0.74, 0.79, and 0.78, respectively. The invariance of the index was significant compared to the original English version.

Conclusion: In general, the results support the adequacy of the psychometric properties of the Persian version of the ASI-3. Theoretical and applied implications will be discussed.