Special needs

Does my kid have ADHD?: Red flags to watch out for

Your kid’s teacher says your child can’t focus or sit still. Could the cause be attention deficit hyperactivity disorder?

Does my kid have ADHD?: Red flags to watch out for

Photo: iStockPhoto

Karen Ryan from Vancouver knew there was something different about her son Eddy from his first day of pre-school. He couldn’t sit still when the teacher played a video during circle time. He constantly went over to sharpen his pencil, and he kept blurting things out instead of waiting his turn. He was the class clown.

When Eddy was seven, his grade two teacher told his mom that his behaviours were getting in the way of his learning and affecting his classmates. She recommended he be assessed for attention deficit hyperactivity disorder (ADHD). A psychiatrist confirmed the diagnosis a few months later, after meeting with Eddy and reviewing questionnaires filled out by his parents and teachers.

Attention deficit hyperactivity disorder is one of the most common mental disorders in children, estimated to affect between five and 12 percent of kids. But for parents of children with ADHD, getting a diagnosis can feel isolating and confusing.

Is it ADHD?

Vanessa Armstrong, a mother of five from London, Ont., noticed differences in her son Aiden as soon as he could walk. “We would joke that he was our runner, because he’d get an idea in his head and off he’d go, without hesitating,” she says.

Aiden’s teachers remarked upon his impulsive nature, and by grade one, Aiden was struggling to keep up with his classmates. Vanessa didn’t think it could be ADHD, because Aiden wasn’t overly inattentive or hyperactive—just impulsive. So when a psychologist thought he had ADHD, Vanessa wanted a second opinion. A psychiatrist confirmed the diagnosis.

As with other mental disorders, including schizophrenia, bipolar disorder and Tourette’s syndrome, there’s no clinical test that can confirm a child has ADHD. Instead, a diagnosis is made when a child shows a pattern of specific symptoms.

Doctors will try to rule out other conditions that could have similar symptoms, including dyslexia, dissociative disorder and personality disorder, before giving an ADHD diagnosis. However, sometimes kids have more than one condition. One study found that as many as two-thirds of kids with ADHD will have a co-morbid condition in their lifetimes, such as anxiety disorder or depression.


An ADHD diagnosis can happen at any age, though doctors usually hold off on prescribing medications until a child turns six. Sometimes, doctors can diagnose a kid as young as three; typically, they’ll want to see a younger child progress for a year or two before drawing any conclusions. A physician makes the diagnosis based on their observations and by learning about behaviour that has been noted by parents and teachers. “Having a diagnosis helps those involved with Aiden to know how to better direct and reach him,” Vanessa says.

There are three different types of ADHD diagnoses, based on which set of symptoms is present. A child can have:

  • ADHD presenting as inattention;
  • ADHD presenting as hyperactivity and impulsivity; or
  • a combined presentation of the first two ADHD subtypes.

DSM-5 criteria checklist

Doctors in Canada use Diagnostic and Statistical Manual of Mental Disorders (DSM-5) guidelines for diagnosing ADHD.

While the criteria are slightly different for adults, children are diagnosed with inattentive ADHD when they have at least six of these nine symptoms for at least six months.

  • Having difficulty sustaining attention during tasks or activities
  • Failing to give close attention to detail or making mistakes
  • Seeming not to listen when spoken to
  • Not following through on instructions and failing to finish schoolwork
  • Having difficulty organizing tasks and activities
  • Avoiding, disliking or being reluctant to engage in tasks that require sustained mental effort
  • Losing materials necessary for tasks or activities
  • Being easily distracted by external stimuli
  • Being forgetful in daily activities

Children are diagnosed with hyperactive and impulsive ADHD when they have at least six of these nine symptoms.

  • Squirming in their seat, fidgeting or tapping hands and feet
  • Leaving their chair when sitting is expected, like at the dinner table or at school
  • Running and climbing in inappropriate situations
  • Being “on the go,” as if “driven by a motor”
  • Talking excessively
  • Blurting out answers before a question has been completed
  • Having difficulty waiting their turn
  • Interrupting or intruding on others
  • Often being unable to play or engage in leisure activities quietly

Children are diagnosed with combined ADHD when they have at least six symptoms from a mix of both categories.

How ADHD presents differently in boys and girls

Attention deficit hyperactivity disorder affects both girls and boys, though the typical presentations vary. Girls with ADHD are more likely to have challenges focusing, while boys are more likely to be restless and impulsive.

This may account for why ADHD is diagnosed about three times more often in boys. After all, the grade two teacher who is very concerned about a restless boy may be less likely to complain about the girl who sits nicely but can’t pay attention.

“The highly inattentive, unfocused little girl is, from a public health perspective, just as much of a concern as the disruptive little boy,” says Russell Schachar, a psychiatrist at Toronto’s Hospital for Sick Children.

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