This article from Psychology Today is over a year old, but a great resource for anyone wondering if ADHD is over diagnosed, under diagnosed, and likewise, over or under medicated:
Symptoms of ADHD can exist independently, and sometimes they coincide with other issues. Alternatively, other symptoms may look like ADHD but in fact are the result of a different underlying issue (for example, anxiety, stress, depression). Therefore, testing for ADHD is comprehensive and often includes a clinical interview, collateral interviews with parents and teachers, record review (if possible), behavior rating scales, measurement of intelligence, objective measurement of attention and impulsivity, and other psycho/emotional rating scales.
In other words, there are several other issues that need to be ruled out, and testing usually takes anywhere from 4-7 hours. Psychologists do not simply run down a symptom checklist to determine if an individual meets criteria. There are many other factors possibly at play and these must be fully explored.
Dr. Lawing provides ADHD testing for children and adults. Please call 504-289-5995 for a free testing consult to determine if psychological testing is warranted.