As described above, although this diagnosis may first be given in adulthood, ADHD begins in childhood. As a result, diagnostic criteria for ADHD in adults are identical to those for children. Clinicians must first verify the presence of ADHD symptoms in childhood by administering questionnaires and reviewing school report cards (if available) to look for comments about behavior problems, poor focus, and lack of effort or underachievement relative to the student's potential. A clinician might also ask to obtain a complete developmental history from the adult by talking with his or her parents (if practical) to obtain additional details about any ADHD symptoms that were present. A developmental history consistent with ADHD would include evidence of problems with peers; problems such as bed wetting, school failure, and suspensions; and special interventions such as sitting in front of the class, etc. A strong family history of ADHD may also be informative, given the strong genetic component of the disorder.
Once a complete developmental history is obtained, other examinations may also be performed, including:
- A physical exam to rule out medical or other causes for the symptoms (e.g., hyperthyroidism, hearing loss, bipolar disorder, substance abuse, depression, etc).
- Brain scans or brain imaging techniques (e.g., EEG, CT, or MRI) to rule out brain abnormalities (that are not consistent with ADHD).
- Psychoeducational testing (e.g., IQ tests and/or achievement tests) if a learning disability or other cognitive deficit is suspected.
The diagnosis of ADHD in adults is challenging because obtaining historical information is often difficult. Trying to remember life events from childhood, particularly if the length of time between evaluation and the age of 7 is long, can cause problems in obtaining accurate information. In addition, most adult clinicians, who are most often the ones providing the evaluation, are not particularly well-versed in childhood psychopathology. Because of these challenges, it is important that the adult is diagnosed by a mental health professional who specializes in working with ADHD.
The following screening tools provide an objective set of questions to structure the memory recall process about childhood symptoms and difficulties. The results from these tools are not sufficient for a diagnosis, but the information they provide can be extremely helpful in the diagnostic evaluation.
Barkley's Adult ADHD Quick Screen
This is a new self-report screening tool used to identify adults who may need further evaluation for ADHD. The scale consists of 13 questions, scored on a scale from Never (0) to Very Often (3). A cutoff score of 9 (out of 27 possible) suggests a very high likelihood that a person has ADHD.
Connors' Adult ADHD Rating Scales (CARRS)
These scales can be used to assess inattention, hyperactive-impulsive behaviors, and overall ADHD symptoms in adults over 18 years of age. CAARS include forms for self-reports and observer ratings that allow for information gathering from more than one source. Obtaining information from different people can improve accuracy of the results. Both versions contain 66 items, including 9 subscales. The scale also includes a measure to determine those respondents who might benefit from a more detailed assessment.
Brown ADD Scales (Adult)
This 40-item self-report measure is a quick way to screen for adult ADD. The instrument highlights 6 target areas: the ability to: sustain attention, sustain effort for completing tasks, activate and organize work tasks, recall learned material, utilize short-term memory, and regulate moods.
Copeland Symptom Checklist for Attention Deficit Disorders - Adult Version
This checklist is designed to determine if an adult (18 and older) has sufficient characteristic symptoms to consider an ADHD diagnosis. Similar to the children's version, the Copeland Symptom Checklist also assesses the severity of symptoms. Eight topic areas are targeted, including: Emotional Difficulties, Peer Relations, Family Relationships, Attention skills, Impulsivity, Activity Level, Disorganization or Learning Problems, and Degree of Compliance.
Wender Utah Rating Scale (WURS)
The Wender Utah Rating Scale assesses ADHD-relevant childhood behaviors and symptoms in adults. Originally, this scale consisted of 61 items, but it has been reduced to 25. The WURS not only distinguishes between individuals with and without ADHD, but also differentiates between individuals with ADHD and those with Major Depression. There is some suggestion that this scale may help differentiate between individuals who will respond to methylphenidate (Ritalin) and those who will not.
As previously discussed, intellectual information can be helpful in the ADHD diagnostic process by revealing an individual's intellectual strengths and weaknesses. A person's pattern of performance can be compared to the typical intellectual pattern of individuals with ADHD (e.g., relative strengths in areas that do not require concentrated effort, such as general information and vocabulary; and weaknesses in subtests that require focused attention such as mathematical computation and pattern recognition). These performance patterns are consistent enough across individuals with ADHD that they can be used as part of a comprehensive evaluation to determine an accurate diagnosis.
Wechsler Adult Intelligence Scale (WAIS)
The WAIS is an adult version of the WISC intelligence test described previously. Each Weschler test evaluates the subject in two areas: Verbal skills and Performance skills. Scores in both of these areas are used to arrive at a Combined Score (the so-called IQ score), which can be used to compare an individual to others (the average IQ score is 100). These tests assess factual knowledge, spatial skills, logical thinking and mathematical abilities.
Wechsler Memory Scale, Third Edition (WMS-III)
The WMS-III is a battery of adult memory tests for use with individuals ranging in age from 16 to 89 years. The test consists of 11 subtests (6 primary and 5 optional subtests). The primary subtests assess logical memory (memory for stories), verbal paired associates (memory for word pairs), letter-number sequencing, and various tasks related to visual memory. The optional subtests assess information and orientation, memory for lists of words and numbers, and other related memory tasks.