Characteristics of included studies.

TTM, trichotillomania; BDD, body dysmorphic disorder; AUD, alcohol use disorder (abuse or dependence); CON, control subjects; DUD, drug use disorder (abuse or dependence); GAD, generalized anxiety disorder; MDD, major depressive disorder; OCD, obsessive compulsive disorder; PD, panic disorder; SAD, social anxiety disorder; SP, specific phobia; AG, agoraphobia;SSRI, selective serotonin reuptake inhibitor; SNRI, serotonin and noradrenaline reuptake inhibitors; BEN, benzodiazepine; TCA, tetracyclic antidepressant. *subgroup analysis within the same study as it showed with the same serial-number