Obsessive-compulsive disorder (OCD) affects roughly 1.2% of the UK population, equating to 12 in 1000 people. “OCD is often thought of in individuals who like order and symmetry, however, it is much more than that,” Dr Sarah Crawford, counselling psychologist at Nightingale Hospital, tells HuffPost UK. “There is often a hidden side to OCD which leads to intense distress and feelings that one is going mad in some way.