State-Trait Anxiety Inventory

The State-Trait Anxiety Inventory (STAI) is a 40-item self-report questionnaire designed to measure two distinct dimensions of anxiety: state anxiety (temporary anxiety in response to a specific situation) and trait anxiety (stable tendency to experience anxiety across situations). Developed by Charles D. Spielberger and colleagues in 1970, the STAI has become one of the most widely used research instruments for differentiating situational from dispositional anxiety in clinical and non-clinical populations.