Even as a toddler, a little boy named Lee was super active. He didn't have time for crawling. No, he started walking at about 9 months.

And he took off after that. Literally. The boy preferred to zoom through the world. Taking naps during his pre-school years just didn't happen. Then sitting in a chair at school was almost tortuous.

And it wasn't just his body that seemed to be in constant motion - except when watching television. His mind was everywhere. Playing with a pencil was far more fascinating than doing math problems.

To say he was a challenge for his teachers and parents is sort of an understatement.

His fourth grade teacher knew what was wrong.  Lee was diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) and prescribed medication that year.

The boy's behavior both in and out of the classroom and his grades improved measurably.

This youngster is one of millions of children, adolescents and adults who wrestle with ADHD.

A new study suggests that ADHD is more prevalent than ever, and dailyRx.com talked with an expert in the field about the latest findings.

What is ADHD and how is it diagnosed?

Attention deficit hyperactivity disorder is one of the most common and well-studied of all childhood conditions. Its symptoms are fairly obvious and include trouble paying attention and focusing, impulsive behavior and hyperactivity.

Symptoms can begin in childhood and persist into adolescence and adulthood. ADHD can - and usually does - impact a person's family, school, social and professional lives.

Diagnosing ADHD involves a number of steps, which include:

• A medical exam
• An assessment checklist that identifies and rates ADHD symptoms
• For children, this checklist is completed by parents, teachers, and sometimes the child.
• Identifying and evaluating other mental health conditions that may be present such as anxiety, depression, etc.

ADHD diagnoses on the rise

A recently published report by the Centers for Disease Control and Prevention (CDC) shows a marked increase in the number of children who are being diagnosed with ADHD between the ages of 5 and 17.

Here's what the National Health Interview Survey, 1998–2009 found:

• The number of children diagnosed with ADHD rose from 7 percent in 1998–2000 to 9 percent in 2007–2009.
• From 1998 through 2009, prevalence of ADHD rose to 10 percent of children from families whose income fell below the poverty line.
• Prevalence rose to 11 percent for those with family incomes of between 100-199 percent of the poverty level.
• ADHD diagnoses increased to 10 percent of children living in the Midwest and Southern regions of the United States.
• These statistics held true for both boys and girls.
• ADHD is consistently less prevalent in Mexican children than in other racial and ethnic groups.