Attention Deficit Hyperactivity Disorder is a neurobiological disorder that is characterized by serious impairment in attention and organization as well as poor self-regulation. The two subtypes, inattentive type and hyperactive-impulsive type, are the most commonly diagnosed behavioral disorders in the United States.
Temperament, on the other hand, refers to normal variations in behavioral style along a number of separate dimensions, including several that appear to overlap with ADHD: activity level, distractibility, persistence and adaptability. Dr. William Carey, Director of Behavioral Pediatrics at the University of Pennsylvania School of Medicine believes that temperament differences are being misdiagnosed as ADHD, leading to the treatment of normal children with powerful stimulant medications.
There are a number of reasons for overdiagnosis, including the annoyance that parents feel when children are inflexible, distractible and nonpersistent, the desire of pediatricians and other health care professionals to help parents, and the frequent use of the diagnosis of ADHD in spite of the absence of all the markers needed to make the diagnosis.
Part of the confusion rests with conceptual deficiencies in the Diagnostic and Statistical Manual (DSM-IV) definitions of normal and abnormal. Dr, Carey believes that "many normal variations of temperament are overdiagnosed, such as an inattentive child who is functioning normally, but who is supposed to be given the 'subthreshold' diagnosis of 'attention-deficit/hyperactivity disorder, not otherwise specified,' rather than simply being considered normal.*"
Behavior is based on interactions between the child and environment, and can be problematic even though there is no 'disorder' causing it. The solution advocated by Dr. Carey: "If the friction is coming from such a disharmonious interaction, the appropriate management consists of (1) recognition of the true nature of the dissonance, (2) revision of the understanding and management by the caregivers, and (3) some suggestions to the parents and others on how to find relief from their own feelings of stress.*"
* Quotes above taken from (Carey et al. (eds.): Developmental-Behavioral Pediatrics, 4th Ed. Philadelphia. Saunders. Elsevier. 2009).