To make an accurate and complete diagnosis, these other possible causes which produce symptoms that mimic ADHD need to be considered and ruled out. It is possible that ADHD is only one part of the diagnostic picture, and that in addition to ADHD there are other coexisting disorders involved. This is, in fact, very common. There is a high rate of comorbity with ADHD. This means that all of the coexisting problems/disorders need to be identified in order to provide proper treatment. Dr. Christopher Green, a specialist pediatrician, has studied many cases involving ADHD and works with children who have ADHD. In his book Understanding ADHD, he mentions what some of the ADHD lool-alikes may be. For example intellectual disabilities, hearing impaired, depression, autism, learning disabilities, epilepsy, brain injury, speech, and language disorders, even family dysfunction. .
Children and teens with ADHD have limited ability to inhibit their responses and control behavior. Although any one of these behaviors is normal in children at different ages to a certain degree, with ADHD the behaviors far exceed that which is normal. Wendy Moragne, author of Attention Deficit Disorder, explains that "The behaviors that characterize ADHD fall into three main categories: inattention, impulsiveness, and hyperactivity." Those with ADHD will exhibit many of the following characteristics and symptoms in each category, if not all of them. .
The symptoms of inattention can include failure to pay close attention to details or make careless mistakes, does not complete tasks. Has difficulty paying attention when spoken to, is easily distracted and/or forgetful. A person with ADHD may also have difficulty being organized or may have a hard time following several instructions at a time (Yahoo). .
Impulsivity may include blurting out answers, and talking excessively. Has difficulty raising hand, awaiting turn, or begins tasks without waiting for directions.