Description
The PSWQ is a 16-item self-report scale designed to measure the trait of worry. The PSWQ has been found to distinguish patients with generalised anxiety disorder (GAD) from other anxiety disorders. This questionnaire can be used in clinical and non-clinical settings.

Validity
The PSWQ has been validated in student (Meyer, Miller, Metzger, & Borkovec 1990) and clinical samples (Brown, Antony, & Barlow, 1992). This research has demonstrated that those with GAD have significantly higher PSWQ scores than people with other anxiety disorders, such as obsessive compulsive disorder (OCD). Scores on the PSWQ are positively correlated with other measures of pervasive worry (Gillis, Haaga, & Ford, 1995). The PWSQ also has high internal consistency and good test-retest reliability.

Interpretation
Scores range from 16 to 80 with higher scores indicative of higher levels of trait worry. A total raw score is given as output which is converted into three percentiles, comparing the total score to three different samples: An adult community sample (n = 244) showing the client’s score in relation to the normal population (Gillis, Haaga, & Ford, 1995). A social anxiety disorder percentile comparing the client’s score with those with social anxiety (n = 132) and a GAD percentile comparing scores to people diagnosed with generalised anxiety disorder (n = 28), (Turk, Fresco, Mennin & Heimberg (2001). Typically individuals with GAD will score highly on this measure compared to other anxiety disorders.

Developer
Meyer, T. J., Miller, M. L., Metzger, R. L., & Borkovec, T. D. (1990). Development and validation of the penn state worry questionnaire. Behavior Research and Therapy, 28, 487-495.