The symptoms (see below) were required to have been present since before the individual was seven years old, and must have interfered with at least two spheres of his or her (at home and at school or work, for example) over the last six months. The DSM-IV criteria for ADHD were, however, tailored towards the type of symptoms that children would show, and might therefore have underestimated the prevalence of ADHD in adults. In 2013, the newer DSM-5 reviewed some of these criteria, with more lenient requirements for the diagnosis, especially in adults, and the age limit for symptoms first arising raised to twelve years.