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Published on: September 12, 2014
Differential prediction of C0₂challenge response as a function of the taxon and complement classes of anxiety
Kristina J Korte And1, Norman B Schmidt
1Department of Psychology, Florida State University, Tallahassee, FL 32306, USA.
Background:
Anxiety sensitivity (AS) is a trait-like characteristic capturing fears of the experience of anxiety and the potential psychological, somatic, or social consequences associated with anxiety. Recently, research has provided evidence for the latent structure of AS suggesting two discrete types, i.e. a taxonic class and a complement class. Investigations have identified combinations from the 16-items of the Anxiety Sensitivity Index (ASI) that are able to predict the taxon class of AS, referred to as the ASI taxon scales.
Method:
The current study investigated the ability of a new ASI taxon scale, comprised of the seven overlapping items of the previously identified ASI taxon scales, to predict CO(2) challenge responses. This was examined in a sample of 387 nonclinical participants presenting for an AS treatment program. Participants completed a battery of questionnaires and a 20% CO(2) challenge as part of the program.
Results:
Analyses indicated that the ASI taxon scale uniquely predicted CO(2) challenge response, whereas the complement scale did not have a significant association.
Conclusions:
The present study provides the first evidence of the AS taxon having the ability to predict an exaggerated fear response to a novel stressor known to be associated with anxiety psychopathology. Implications of these findings are discussed.
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