According to Faces of Abnormal Psychology's website, 2% of adults in the United States have been diagnosed with obsessive-compulsive disorder (OCD) and about 4% will experience the disorder at some point in their lives. Obsessive-compulsive disorder can begin at any time from preschool to adulthood. Symptoms of the disorder begin gradually, often during adolescence or early adulthood. In children, compulsive actions usually appear first and obsessive thoughts often develop later. Children may express obsessive-compulsive symptoms however, they typically have poor insight and seldom perceive that their compulsive behaviors are excessive. In adults, about one-third of those diagnosed with obsessive-compulsive disorder later report that they began having symptoms during their childhood. Unfortunately, in most cases, their symptoms were unrecognized until later points in their lives.