Affect and worry during a checking episode: A comparison of individuals with symptoms of obsessive-compulsive disorder, anorexia nervosa, bulimia nervosa, body dysmorphic disorder, illness anxiety disorder, and panic disorder.

•Course of affect and worry is transdiagnostically examined during checking episode.•Self-reported negative affect is greater before checking compared to baseline.•Negative affect and worry decrease during checking in OCD, AN, BN, BDD, IA, and PD.•The functions reduction of negative affect and attainment of certainty predict course of affect.•Attainment of certainty emerges as (one of) the most frequently reported functions.