I just read the summary of an article supporting the theory that ADHD is an extreme of the hyperactive behavior seen in "normal" children. The support was based on
images of the brains of ADHD patients compared to non-ADHD children without hyperactive behavior and then to non-ADHD children with some hyperactive behavior. The authors stated that since the findings in the last group of children were in between those of the other two, ADHD was actually just one end of a "dimensional" spectrum. I was not impressed with the summary of their study, but I do think that their premise is useful to consider. (One of my major objections to the study was their focus only on hyperactive behavior. What about inattention?)
Many parents have questioned the validity of using ADHD symptoms to "qualify" for the diagnosis of ADHD by saying "everybody does that sometimes!" Some have even asked if it is possible to have "just a little bit of ADHD." Agreeing with these two statements would imply that ADHD is merely an excess of "normal" behaviors.
In most cases of ADHD the difference between "normal" and "ADHD" is very clear: there are definitely more than 6 symptoms of either inattention or hyperactivity/impulsivity. However, what should be done for someone who has only 5 symptoms and yet is not doing as well as he or she would like in school and has to work twice as long as siblings do to accomplish chores? Purists would claim that such a person does not have a "disorder" because he or she did not fulfill the definition by which the diagnosis is made. Given that determination, a physician would not be able to prescribe medication since the patient did not have a disease. Indeed, some would say that allowing such a patient to take stimulants would be equivalent to prescribing "performance enhancing drugs" to an athlete.
I am not such a purist. I think that it is possible to have "just a little bit of ADHD." If a person has some symptoms and is experiencing problems in two areas of life, I think that a trial of ADHD medicine is useful. Of course, a medicine should not be used if it causes side effects nor should it be used just for testing or for big projects. (The latter use is typical of how stimulants are abused by college students for whom it is not prescribed.) As with any medical intervention, the benefits must outweigh the risks both to the patient and to society.