A major study of 1.16 million six to 19 year-olds has found strong links between receiving medication for attention deficit hyperactivity disorder (ADHD) and limited maternal education, single parent families and welfare benefits. It is believed to be the first study of risk factors for ADHD in a national cohort of school children. Women who had only received the most basic education were 130% more likely to have a child on ADHD medication. Children were 54% more likely to be on ADHD medication if they came from a single parent family. Coming from a family on welfare benefits increased the risk of ADHD medication by 135%.