[The Inventory "State-Trait Operation Anxiety" (STOA): construction and empirical findings]

This article reports on the construction and empirical evaluation of an instrument for the measurement of surgery-related state and trait anxiety. The inventory "State-Trait Operation Anxiety" (STOA) separately assesses surgery-related anxiety as a comparatively stable personality trait as well as the cognitive and affective components of state anxiety. Results of explorative and confirmatory factor analyses corroborated the unifactorial structure of trait anxiety and the two-factorial structure of state anxiety. Internal consistencies of all scales were highly satisfactory (Cronbach's alpha around 0.90). External relationships of the STOA with trait anxiety, dispositional and actual coping, observed anxiety, as well as indicators of perioperative adjustment confirmed the inventory's validity. An analysis of the scores of the two state anxiety components across the perioperative period demonstrated that these scales are sensitive indicators of state anxiety changes.