Development and psychometric evaluation of a scrambled sentences test specifically for worry in individuals with generalised anxiety disorder

The tendency to draw negative conclusions from ambiguous information (interpretation bias) is prevalent across emotional disorders and plays a key role in the development and maintenance of pathological worry and anxious mood. Assessing interpretation bias using valid and reliable measures is central to empirical research. A commonly used measure of interpretation bias is the scrambled sentences test (SST), originally relating to depression. Given the association between interpretation bias and worry, we aimed to develop and psycho-metrically evaluate a new version of the SST with items pertaining to common worry domains for use in worry and anxiety research. In Studies 1-3 (analogue samples, combined N = 288), the new worry SST showed excellent construct validity (moderate-to-strong associations with worry and anxiety-related measures), and reliability (split-half and test-retest reliability). We confirmed construct validity in Study 4 (N = 215 individuals with generalised anxiety disorder). Furthermore, we demonstrated version specificity in analogue and clinical samples: the worry SST was associated with trait worry but not trait rumination, while the original depression SST largely showed the opposite pattern. Overall, the new worry SST is a psychometrically robust measure that may be especially useful for research into cognitive processes underpinning worry and anxiety.