Dimensionality, Reliability, Invariance, and Validity of the Multidimensional Social Anxiety Response Inventory-21 (MSARI-21).

Research shows that social anxiety disorder (SAD) is prevalent in the United States, and could interfere with many aspects of a person's life. Although numerous psychological instruments have been developed to measure presence and intensity levels of social anxiety, these instruments fail to capture the range of responses individuals use to mitigate the negative affect associated with the anxiety, namely alcohol use and anger distress. Recently, the Multidimensional Social Anxiety Response Inventory-21 (MSARI-21) was developed to address this limitation and increase our understanding of the complexity of social anxiety. We expand on this work by evaluating the psychometric properties of the instrument, using a combination of exploratory structural equation and bifactor modeling, and item response techniques. Across 2 studies, data indicated the presence of a strong, 3-factor structure (i.e., anger distress, alcohol reliance, and social avoidance), strong internal consistency, and evidence of both convergent and discriminant validity. In addition, results showed that the MSARI-21 multidimensional structure was invariant across gender. We conclude that the MSARI-21 is a valid and valuable tool for assessing individuals' responses to social anxiety, and that future research should evaluate the instrument within other samples to ensure its utility across clinical and subclinical populations.