How is ADHD Assessed?

Medical Exam

The medical exam can help rule out any physical reasons for the inattentive and/ or hyperactive-impulsive behavior, such as thyroid problems or brain tumors. The physician can determine whether the child's behavioral problems are due to a seizure disorder, such as epilepsy. Environmental factors, such as lead poisoning, can also be considered.

The physician can also determine whether the patient has other conditions that would make it unwise to prescribe certain medications to help control the inattention or hyperactivity. For example, high blood pressure, cardiac problems, or asthma might influence what kind of medication the doctor would prescribe for the child. And if the child has tics, the physician might be more careful in using certain medications, because there is suggestive evidence that commonly used medications for ADHD might make the tics worsen. Tics are repetitive motor movements that are sometimes accompanied by multiple vocal grunts or outbursts. Severe tics are one of the major symptoms of someone who has Tourette's syndrome. There is a high incidence of ADHD in individuals diagnosed with Tourette's syndrome.

Clinical Interview

The clinical interview, or history of the child and parent(s), is important because it can be used ,to gather information on the child, the parents, and any siblings. The clinician can obtain a picture of the dynamics of the family and the major symptoms that all the family members see as most problematic.

Even though the interview is important, we need to recognize that it is somewhat subjective. For example, some children with ADHD can appear very attentive when in a structured and novel setting. In fact, researchers have discovered what has been referred to as a doctor's office effect, whereby children can be focused in the physician's office but just the opposite at home and school (Cantwell, 1979; Sleator & Ullman, 1981).

Rating Scales

Because of the subjectivity of the clinical interview and the existence of such things as the doctor's office effect, professionals often use rating scales to obtain more objective, behavioral data.

As noted in the Case Connections box, Jamal's pediatrician used rating scales to help determine that Jamal was not ADHD. The rating scale he used, the Conners' Teacher Rating Scale-Revised (S) (Conners, 1997), is one of the most commonly used standardized rating scales. As we noted earlier, Shannon's psychiatrist, Dr. Roodriguez, used an informal checklist, or rating form, based on the DSM criteria, to help in the diagnosis of Shannon's ADHD. But Dr. Rodriguez also requested that Shannon's teacher fill out one portion of the Conners' scale. (Recall that, according to the DSM, symptoms of ADHD should be observed in at least two settings.) The ratings on this scale were in agreement with those of the parents. Her teacher rated her as highly inattentive but not very hyperactive on this 28-item rating scale. (There is a longer version of this rating scale that contains 59 items.)

Using Technology to Assess ADHD

Although medical exams, clinical interviews, and rating scales will probably always be a necessary part of the identification of students with ADHD, researchers are turning to technology to find additional methods of assessing ADHD. For example, there are several commercial computerized versions of continuous performance tests (CPTs). CPTs vary somewhat. A typical one projects stimuli (e.g., Xs and Os) one at a time on a screen rapidly (about one per second), and the individual is instructed to push a button every time a particular stimulus (e.g., X) appears or a particular sequence (e.g., 0 followed by an X) appears. The computer keeps track of the number of correct responses, failures to respond to a correct stimulus (omission errors), and incorrect responses or responses to the wrong stimulus (commission errors).

It has now become relatively common for clinicians to use a computerized CPT to help evaluate children for ADHD. There are other technologies that hold potential for helping identify ADHD that are much more experimental.

Issues Related to Identification for Special Education Services

The overlap between learning disabilities and ADHD has created considerable controversy in the field. This controversy has made it difficult to keep track of how many students with ADHD are served in special education. Furthermore, it makes it difficult to keep track of such things as the gender and ethnicity of students identified as ADHD and receiving special education. This is unfortunate, because some have claimed that African American boys are disproportionately identified as ADHD.