Fear of physical sensations and trait anxiety as mediators of the response to hyperventilation in nonclinical subjects.

Three studies were conducted to compare the ability of a measure of fear of physical sensations (Anxiety Sensitivity Index; ASI) and a measure of trait anxiety (State-Trait Anxiety Inventory; STAI) to predict response to hyperventilation. In the first study subjects (N = 43) were selected who differed in scores on the ASI but were equated on levels of trait anxiety. Two other studies were conducted in which subjects (ns = 63 and 54) varied randomly on ASI and STAI scores. The results indicate that scores on the ASI account for a significant proportion of variance in the response to hyperventilation that is not accounted for by scores on the STAI.