The Centers for Disease Control and Prevention (CDC) estimate that 11 percent of 4-17-year olds in the United States have attention deficient hyperactive disorder (ADHD). The CDC also estimate that in the U.S., boys are almost 3 times more likely to be diagnosed with ADHD than girls are. This has led to the mistaken belief among many parents, caregivers, and teachers that ADHD is a "boys' disorder" that rarely occurs in girls.