The Contribution of Worry Behaviors to the Diagnosis of Generalized Anxiety Disorder.

Worry behaviors (i.e., overt acts to avoid or cope with worry-induced distress) have been recognized as being important in the psychopathology and treatment of generalized anxiety disorder (GAD). This study evaluated the worry behaviors criterion proposed for GAD, but was ultimately not adopted due to insufficient evidence. In 800 outpatients with emotional disorders (366 with GAD), most patients with GAD (92.6%) met the proposed worry behaviors criterion, which was at a rate significantly higher than other patient groups (e.g., patients with mood disorders). Patients who met the worry behaviors criterion had more severe GAD than patients who did not. The worry behaviors criterion, and 3 of its 4 constituent behaviors, were associated with no better than "fair" interrater reliability. Diagnostic reliability of GAD was not improved in cases where both interviewers agreed the worry behaviors criterion was met. The worry behaviors criterion significantly predicted GAD holding core GAD features constant (e.g., excessive worry), but this contribution was weak and did not appreciably improve the classification accuracy of GAD diagnostic status. Mixed support was obtained for the discriminant validity of the worry behaviors criterion in relation to mood disorders. Raising the proposed threshold of the criterion (requiring 2 instead of 1 behaviors) did not result in a substantial improvement in reliability, prediction, and classification accuracy. Although additional research is warranted (e.g., importance of worry behaviors in the treatment and natural course of GAD), the results raise questions about the role of worry behaviors in the diagnostic classification of GAD.