Measurement Invariance of Disorder-Specific and Transdiagnostic Measures of Repetitive Negative Thinking.

The Ruminative Response Scale, Penn State Worry Questionnaire, and Repetitive Thinking Questionnaire are measuring trait repetitive negative thinking in a consistent manner across individuals with a principal diagnosis of depressive disorder, social anxiety disorder, or generalized anxiety disorder. This supports their use in transdiagnostic contexts and indicates that it is appropriate to directly compare the scores on these measures between diagnostic groups.