Worry and the anxiety disorders: A meta-analytic synthesis of specificity to GAD

Although worry is central to the diagnosis of generalized anxiety disorder (GAD), it is also commonly observed in other anxiety disorders. In this meta-analytic review, we empirically evaluated the extent to which worry is specific to GAD relative to patients with other anxiety disorders, those with other psychiatric disorders, and nonpsychiatric controls. A total of 47 published studies (N = 8,410) were included in the analysis. The results yielded a large effect size indicating greater severity/frequency of worry, meta-worry, and domains of worry among anxiety disorder patients v. nonpsychiatric controls (d = 1.64). In contrast to the many differences emerging from comparisons between anxiety disordered patients and nonpsychiatric controls, when anxiety disordered patients were compared to people with other psychiatric disorders they differed only on severity/frequency and not on meta-worry or domains of worry. A large effect size indicating greater severity/frequency of worry, meta-worry, and domains of worry among patients with GAD v. nonpsychiatric controls was also found (d = 2.05). However, differences between GAD and those with other psychiatric disorders also emerged for severity/frequency of worry. GAD was associated with greater worry difficulties than other anxiety disorders, which generally did not differ from those with other psychiatric disorders and each other. The implications of these findings for conceptualizing worry in GAD and other anxiety disorders, and the potentially moderating effects of age and gentler are discussed. (C) 2011 Elsevier Ltd. All rights reserved.