Researchers have developed a brief scale to screen for adult attention-deficit/hyperactivity disorder (ADHD) using Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria.
The process of developing the scale involved use of a novel machine-learning algorithm.
"The new scale is short, easily scored, and can detect the vast majority of adult attention deficit/hyperactivity disorder cases in the general population with high sensitivity and specificity, discriminating well among patients presenting for evaluation and specialty treatment," the authors, led by Berk Ustun, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, write.
The tool is described in an article published online April 5 in JAMA Psychiatry.
Rapid Rise in Adult ADHD
Evidence shows that there has been a rapid increase in ADHD among adults as well as children. Recent changes to diagnostic criteria in the DSM-5 will likely lead to further increases.
Such changes include lowering the number of symptoms for diagnosis in adults from six to five and raising the age at onset of childhood symptoms from 7 years to 12 years.
In addition, there is less emphasis on clinically significant impairment and more emphasis on symptoms that interfere with or lower the quality of day-to-day functioning.
Although experts increasingly recognize that adult ADHD is common and is associated with comorbid mental illness, workplace impairment, and early mortality, the condition often goes undiagnosed.
For the study, researchers used three samples – a household sample from the National Comorbidity Survey Replication, a national face-to-face survey; a managed care sample based on a telephone survey of subscribers to a large managed healthcare plan; and a sample of patients who obtained a free evaluation at the New York University Langone Medical Center Adult ADHD Program.
The Adult ADHD Self-Report Scale (ASRS) was developed by psychiatrists working with a World Health Organization (WHO) advisory group to generate one fully structured question from each DSM-IV criterion symptom of inattention and hyperactivity-impulsivity, plus 11 non-DSM-IV symptoms of deficits in higher-level executive function believed to be relevant to adults ADHD.
Each question asked how often the symptom occurred during the past 6 months.
The researchers aimed to create a DSM-5 screening scale that had the same form as its DSM-IV counterpart – a simple additive scale with a limited number of variables and integer scoring for quick calculation. They used the Risk-Calibrated Super-sparse Linear Integer Model.
This machine-learning algorithm makes it possible to develop "short integer-scored screening scales more rigorously by using modern optimization techniques that find a best-fitting logistic regression model with a fixed number of screening questions and optimal integer scoring of each response option to predict clinical outcomes," the authors write.
The new machine-learning algorithm was able to build a screening scale for DSM-5 adult ADHD from responses to six questions in the WHO ASRS screening scale.
The screen's questions are as follows:
How often do you have difficulty concentrating on what people say to you, even when they are speaking to you directly? (DMS-5 A1c)
How often do you leave your seat in meetings or other situations in which you are expected to remain seated? (DSM-5 A2b)
How often do you have difficulty unwinding and relaxing when you have time to yourself? (DSM-5 A2d)
When you're in a conversation, how often do you find yourself finishing the sentence of the people you are talking to before they can finish it themselves? (DSM-5 A2g)
How often do you put things off until the last minute? (non-DSM)
How often do you depend on others to keep your life in order and attend to details? (non-DSM)
Responses can be never, rarely, sometimes, often, or very often. The "never" response is always scored as 0; the highest scores are 5 for questions 1 and 2, 4 for question 5, 3 for question 6, and 2 for question 4, resulting in a scale with scores ranging from 0 to 24.
During clinical interviews, 637 study participants from the subsamples were administered a semistructured research diagnostic interview for DSM-5 adult ADHD.
The new scale yielded high specificity and positive predictive values. About 67.3% of participants screened positive in the general population. More than 80% in the specialty treatment sample who screened positive were confirmed as having the disorder, at a threshold that had sensitivity greater than 90%. The scale yielded few false positive results.
"The new DSM-5 ASRS screening scale showed excellent operating characteristics, given that it correctly classified nearly all people who met diagnostic criteria for ADHD in clinical interviews both in the general population (where prevalence was low and cases were often mild) and in the speciality setting (where prevalence was high and cases were often severe)," the authors note.
It would be useful to validate the screening scale in other samples, such as primary care and workplace case-finding samples and subsamples of patients with presenting symptoms consistent with adult ADHD, the authors write.
As public awareness of adult ADHD increases, so too does the need for psychometrically robust screening tools, Philip Shaw, PhD, Social and Behavioral Research Branch, National Human Genome Research Institute, Bethesda, Maryland, and colleagues note in an accompanying editorial.
They add that two of the six screening items that best predicted diagnosis were associated with chronic procrastination and a dependence on others to keep life in order, which "are not ADHD symptoms per se."
Such items, they note, have previously been found to be superior to ADHD symptoms in predicting the DSM-IV diagnosis of adult ADHD.
"Such findings raise the issue of whether current criteria, designed with children in mind, can adequately capture the expression of ADHD in adulthood."
In the current study, the prevalence of adult ADHD, by DSM-5 standards, was 8.2%, which is much higher than the 4% prevalence reported a little more than 10 years ago by the same group using similar approaches, the editorial writers note.
They add that the current study maintains the DSM-5 requirement that some symptoms of ADHD have to be present before age 12 years, but that recent studies found that symptoms of ADHD in adults were more likely to have started in adulthood than childhood.
"These fascinating findings will not only stimulate further research but could also result in less insistence on a childhood history of symptoms, perhaps even further increasing diagnostic rates."
The authors of the study have numerous ties to industry, as listed in the original article. The editorialists have disclosed no relevant financial relationships.
Medscape Medical News © 2017
Cite this: Brief Screening Tool for Adult ADHD Released - Medscape - Apr 19, 2017.