Worrying about Worry: Measuring and Modelling Metacognition in Children and Adults with Generalised Anxiety Disorder

Abstract

Wells’ (1995) metacognitive model proposes that Generalised Anxiety Disorder (GAD) is maintained by the positive and negative beliefs an individual holds about worry, which are exacerbated by maladaptive coping strategies such as attempted thought control. Although studies with adults support many of the predictions of the model, research with clinical samples is lacking. Recent research has supported the extension of this theory to childhood anxiety, however the results have been inconsistent. The aim of this thesis is therefore to investigate and compare the role of metacognitive beliefs and processes in the maintenance of childhood and adult GAD. The components include: a literature review of evidence for the model in adults and children; a systematic review of measures of metacognitions about worry; validation and evaluation of the clinical utility of the Metacognitions Questionnaire - Short Form (MCQ-30) and Revised Metacognitions Questionnaire for Children (MCQ-CR) in adults and children with GAD respectively; and evaluation of the metacognitive model in adults and children with GAD using path analysis. Evidence was found for the reliability, validity and clinical utility of the MCQ-30 and MCQ-CR in people with GAD. The factor structure of the MCQ-CR, however, did not provide a good fit to the data, raising questions about the merits of adapting adult measures for children. The results of the path analyses supported the integral role of negative beliefs about worry in maintaining clinical levels of GAD in adults and children. The roles of positive beliefs about worry and thought control strategies, however, were questioned, most notably for children with GAD. This thesis contributes novel evidence from clinical samples of adults and children with GAD. Further, the findings suggest that more parsimonious measures and models of the metacognitions implicated in GAD may result in more efficient and effective assessment and treatment across the lifespan.