Obsessive-compulsive disorder (OCD) is a common and disabling psychiatric illness characterised by obsessions (repetitive, intrusive, unwanted and distressing thoughts, images, or urges) and compulsions (repetitive behaviours or mental acts that a person feels driven to perform in response to the obsessions, or according to rigid rules) (1, 2). Affecting children as young as 3–4 years old (3, 4), as well as the elderly over 70-years old (5), OCD incidence is generally highest during pre-adolescence (mean onset 11 years), and early adulthood (mean onset 23 years) (6, 7).
