Patients often come into my office to be “tested for ADHD,” and I explain to them that the diagnosis depends on a thorough clinical interview. Nonetheless, rating scales can be useful. The most well known ADHD rating scale is the Conner’s scale (Conners CK, Conners Rating Scales-Revised. Toronto, ON: Multi-Health Systems; 1997), but it may be more appropriate in children than in adults.
Before discussing specific instruments, why should psychiatrists even use questionnaires and rating scales for adult ADHD? I like them for a couple of reasons. First, they save me time by having the patient provide a lot of historical and clinical information that I may not be able to cover during an appointment. Second, a rating scale often provides useful detail on symptoms that I can add to my progress notes. For example, instead of simply stating “Patient reports having a history of poor attention and organization since early childhood,” I can extract a more thorough set of symptoms from the rating scale, thereby transforming a generic statement to something like, “Patient reports difficulty finishing work assignments, often blurts out answers during meetings, often delays completing tasks that require sustained mental effort, feels restless throughout the day, frequently loses important items.”
A well-written scale can also help patients see how their symptoms have changed over time and note their level of improvement with treatment. Patients may also feel like they have another avenue to convey how their symptoms have caused difficulties.
Which adult ADHD scales are easy to use?
A recent review identified 35 validation studies of 14 different adult ADHD rating scales (Taylor A et al, Res Dev Disabil 2011;2(3):924–938). ADHD symptoms scales are available as clinician-administered, observer-rated, or self-report. Because your patients can complete them on their own, self-report scales are probably the most convenient type for a clinic to implement.
Let us take a close look at three widely used ADHD scales.
Conners’ Adult ADHD Rating Scales (CAARS)
The CAARS are two different scales, one for patients (a self-report scale) and one for observers, such as spouses, parents, or co-workers. Clinicians have the choice of using three different length scales: a screening, short, or long version (Conners CK et al, Conners’ Adult ADHD Rating Scales, Technical Manual. New York, NY: Multi-Health Systems; 1999). An advantage of this scale is that you can easily identify all 18 DSM-IV ADHD items. The CAARS were used as the primary outcome measure in a large adult ADHD trial using atomoxetine (Strattera) (Michelson D et al, Biol Psychiatry 2003;53:112–120).
Brown Attention-Deficit Disorder (ADD) Rating Scale for Adults
The Brown Attention-Deficit Disorder (ADD) Rating Scale for Adults was developed prior to the development of the DSM-IV ADHD criteria (Brown TE, Brown Attention-Deficit Disorder Scales. San Antonio, TX: The Psychological Corporation; 1996). The scale was designed using symptoms reported by high school and college students with ADHD (non-hyperactive). The Brown ADD scale evaluates five symptom domains including work, sustaining alertness and effort, sustaining attention and concentration, working memory, and managing frustration. A score greater than 50 is suggestive of an ADD diagnosis (4% false negative rate and a 6% false positive rate in adult ADD) (Weiss M et al, ADHD in Adulthood. Baltimore, MD: The Johns Hopkins University Press; 1999).
The ADHD Rating Scale with Adult Prompts (ADHD-RS-IV)
The ADHD Rating Scale, Version IV (ADHD-RS-IV) is the most widely used outcome measure in clinical trials of ADHD treatments in children and adolescents (Spencer TJ et al, Clin Ther. 2006;28(2):266–279; Collett BR et al, JAACAP 2003;42(9):1015–1037). An adult version has been validated, and it is called the ADHD-RS-IV with Adult Prompts (Adler LA et al, J ADHD Relate Disord 2009;1(1):14–24). The 18-item scale is based on the DSM-IVTR criteria for ADHD, and scoring is on a fourpoint Likert-type severity scale of zero to three (none, mild, moderate, severe) (DuPaul GJ et al, ADHD Rating Scale-IV: Checklists, Norms, and Clinical Interpretation. New York, NY: Guilford Press; 1998).
This is the scale that I have found most useful in my practice, because it is easy to score and track symptom improvement. Patients also find it helpful because the prompts include questions that are designed specifically for adults and multiple questions are listed for each symptom.
The ADHD-RS-IV with Adult Prompts was correlated with the Clinical Global Impression of Severity/Improvement (CGI-S/I) from a clinical trial of lisdexamfetamine (Vyvanse) in adults with ADHD (Goodman D et al, Primary Psychiatry 2010:17(3):44–52).
Using the data from the adult lisdexamfetamine trials I have found the following scoring system to be helpful for the ADHD-RS-IV with Adult Prompts.
28–36 = Mild
37–41 = Moderate
42–54 = Severe
10 = Minimal Improvement
25 = Much Improved
33 = Very Much Improved
TCPR’s VERDICT: ADHD scales save time and improve care.