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Full list of author information is available at the end of the articleBackground Obsessive-Compulsive Disorder (OCD) is a severe and incapacitating disorder associated with intense anxiety, high degrees of psychiatric comorbidity, and significant health and social costs [1]. The disorder is recognised as a leading cause of disability [2] with levels of impairment similar to that of patients with schizophrenia [1]. OCD is characterised by the presence of obsessions and/or compulsions [3]. Obsessions are unwanted ego-dystonic thoughts, images or urges that are recurrent, persistent and intrusive, and that lead to marked distress. Compul-sions are repetitive, rigid intentional behaviours or men-tal acts performed to reduce distress that follows an obsession, or to avoid potential danger [3]. OCD is a highly complex and heterogenous disorder with differen-tial treatment outcomes for its various presentations [4]. * Correspondence