There's no single test to diagnose ADHD. Instead, doctors rely on several things, including:
- Interviews with the parents, relatives, teachers, or other adults
- Personally watching the child or adult
- Questionnaires or rating scales that measure symptoms of ADHD
- Psychological tests
The doctor needs to see how much a person’s symptoms are affecting their daily moods, behavior, productivity, and lifestyle habits. And they need to rule out other conditions.
With children, the doctor will talk with the parents about ADHD symptoms they have seen. The doctor will want to know what age the behaviors began and where and when the child shows symptoms. The doctor may ask for a behavior report from the child's teacher, report cards, and samples of schoolwork.
With adults, the doctor may want to talk with a spouse or other family members. They'll want to find out if the patient had symptoms in childhood. Knowing if an adult had ADHD behavior as a child is important for making a diagnosis.
To rule out other conditions, a doctor may ask for tests, including:
- Hearing and eyesight
- A blood test for lead levels
- A blood test for diseases such as thyroid disease
- A test to measure electrical activity in the brain
- A CT scan or MRI to check for brain abnormalities
What Doctors Look For
To diagnose ADHD, doctors most often use guidelines established by the American Psychiatric Association. The group has identified 3 types of the disorder:
1. Inattentive Type: A person must have at least 6 out of these 9 symptoms, and few symptoms of hyperactive-impulsive type:
- Doesn't pay attention to detail or makes careless mistakes
- Doesn't stay on task
- Doesn’t listen
- Doesn’t follow instructions or finish schoolwork or chores
- Trouble organizing tasks or activities
- Avoids or dislikes doing things that take effort or concentration
- Loses things
- Easily distracted
2. Hyperactive-Impulsive Type: A person must have at least 6 out these 9 symptoms, and few symptoms of inattentive type:
- Fidgets or squirms a lot
- Gets up from their seat a lot
- Runs or climbs at inappropriate times
- Has trouble playing quietly
- Always “on the go” as if “driven by a motor"
- Talks excessively
- Blurts an answer before the question has been completed
- Trouble waiting their turn
- Interrupts others
3. Combined Type. This is the most common type of ADHD. People with it have symptoms of both inattention and hyperactivity-impulsivity.
Along with these APA guidelines, doctors may also use rating scales to help them evaluate and track ADHD symptoms. A few examples are
- The Vanderbilt Assessment Scale. This 55-question assessment tool reviews symptoms of ADHD. It also looks for other conditions such as conduct disorder, oppositional-defiant disorder, anxiety, and depression.
- The Child Attention Profile (CAP). This scale is generally filled out by teachers and tracks common ADHD symptoms.
- Behavior Assessment System for Children (BASC). This test looks for things like hyperactivity, aggression, and conduct problems. It also looks for anxiety, depression, attention and learning problems, and lack of certain essential skills.
- Child Behavior Checklist/Teacher Report Form (CBCL). Among other things, this scale looks at physical complaints, aggressive or delinquent behavior, and withdrawal.
Brain Wave Tests
The Neuropsychiatric EEG-Based Assessment Aid (NEBA) System is a scan that measures brain waves. The ratio of certain brain waves tends to be higher in children and adolescents with ADHD. The scan is approved for use in children ages 6 to 17, but is meant to be used as a part of a complete medical and psychological exam.
Other tests help diagnose other medical conditions that mimic ADHD. But they don’t diagnose ADHD.
From Diagnosis to Treatment
If the doctor makes an ADHD diagnosis, it's important to follow the treatment. The doctor may recommend medications and behavioral therapy. These treatments can bring relief from the symptoms and make ADHD easier to manage.