Pretreatment levels of rumination predict cognitive-behavioral therapy outcomes in a transdiagnostic sample of adults with anxiety-related disorders

•The impact of rumination on outcomes in CBT for anxiety remains unclear.•147 adults seeking treatment for anxiety-related disorders were studied.•Trait rumination was measured before cognitive-behavioral therapy.•Pretreatment levels of rumination predicted quality of life at the end of treatment.•Rumination did not reliably predict clinically meaningful change.