Table 1. Features of OCD, Tics, and their Comorbidity.

	OCD	Tics	OCD with Comorbid Tics
Prevalence	1-3% of youth in the general population	1% of youth in the general population	No prevalence rates have been empirically determined for the general population 20-30% of individuals with OCD have Tics. 22-44% of individuals with Tics have OCD.
Etiology	Childhood onset	Childhood onset	Childhood onset, typically at earlier age than OCD or Tics alone Males have higher rates of comorbidity
Phenomenology	Persistent, intrusive, and inappropriate ideas, thoughts, impulses, or images that cause anxiety or distress Repetitive behaviors or mental acts that serve to prevent or reduce anxiety or distress	Sudden, rapid, recurrent, non-rhythmic, stereotyped motor movements or vocalizations Classifications include simple versus complex tics and vocal versus motor tics Performed to relieve aversive physical sensation Presence of premonitory urge	Chronic waxing and waning course of symptoms Repetitive behaviors Intrusive sensations Impairment in behavioral inhibition Higher rates of the physical sensations typically only seen in TS preceding or accompanying the cognitive processes surrounding OCD compulsions Increased mental sensations such as “just right” feelings and energy release Higher frequencies of repetitive behaviors preceded by both cognitive and sensory phenomena. Higher rates of compulsions that look like complex motor tics Higher frequencies of hoarding, counting rituals, intrusive violent and sexual thoughts or images, somatic obsessions, and repetitive movement compulsions
Treatment	Exposure and response prevention Psychoeducation Hierarchy development Exposure Relapse prevention Pharmacotherapy may augment treatment response	Habit reversal training Psychoeducation Awareness Training Hierarchy development Competing response strategies Relapse prevention Pharmacotherapy may augment treatment response	Little empirical evidence for standardized treatment protocol Psychoeducation Awareness Training Hierarchy development Exposure Competing response strategies Relapse prevention Pharmacotherapy may augment treatment response