Addressing the Challenge of Under-Diagnosed Adult ADHD

There is a well-documented gap between the known prevalence of adult ADHD and rates of diagnosis and treatment. In Germany, epidemiological studies of nationally representative community samples have found prevalence rates ranging from 3.1% to 4.7%. Yet studies of publicly insured individuals age 18 to 69 years old report rates of diagnosed ADHD between 0.04% and 0.4%. So, even in a country with universal health insurance more than nine out of ten adults with ADHD go undiagnosed.

Many factors contribute to underdiagnosis: stigma, culturally influenced perceptions, and lack of motivation by those affected. Another crucial factor is the lack of recognition of ADHD symptoms by clinicians.

A research team surveyed 144 psychologists, 32 physicians, and two occupational therapists. Almost three in five participants were psychotherapists, a quarter were neuropsychologists, and one in seven were psychiatrists.

Four out of five clinicians stated they had received only “a few hours” of ADHD-specific training. One in four stated they had not examined guidelines for diagnosing ADHD. A lack of formal training among the vast majority and unfamiliarity with current diagnostic guidelines in a significant minority were surprising findings among clinicians who regularly work with adults with ADHD.

Many clinicians had difficulty identifying core features of adult ADHD as defined by the DSM-5 and International Classification of Diseases, Tenth Revision (ICD-10). Roughly one in five stated that hyperactivity had little relevance to adult ADHD. The only core feature correctly identified by more than half the respondents was having “difficulties concentrating.” Impairments in social behavior or aggression and memory impairment were not identified as being clearly “relevant” or “irrelevant” to adult ADHD.

The authors concluded, “these findings appear to indicate some uncertainty or at least a lack of consensus among clinicians about what symptoms are relevant to ADHD in adulthood and it is likely that this uncertainty contributes to diagnostic inaccuracy.”

Most respondents reported using self-report scales of ADHD symptoms and using unstructured interviews. While slightly more than half agreed that collateral reports are important to diagnosis, only about a third reported regularly using them. This is a problem given the limited accuracy of self-reported childhood symptoms for documenting the childhood-onset of the disorder. Semi-structured interviews are also known to improve the accuracy of diagnosis but are rarely used in clinical practice.

Over half of psychologists and a quarter of physicians reported using cognitive or neuropsychological testing, even though this is at variance with German (and other) guidelines, which specify that such testing is suitable for clarifying strengths and weaknesses, but not for ruling out or confirming a diagnosis of ADHD. The European Consensus Statement also states that cognitive/neuropsychological testing should only be used as a secondary or supplementary assessment tool.

While three out of four clinicians recommended stimulant drug treatment, psychologists tended to be more hesitant to do so. This is likely because German psychologists receive little training in pharmacotherapy, and do not have prescription privileges. Given the demonstrated efficacy of stimulant treatment, this points to a need to better educate psychologists in this regard.

Almost three in four respondents cited “lack of clinician knowledge and experience” as a barrier to ADHD diagnosis. Most clinicians also stated they were either “uncertain” or only “somewhat certain” of their ability to diagnose ADHD. That suggests that more extensive ADHD-specific training is needed.

A limitation of the survey was the relatively low participation by physicians. It is also likely that the findings are not reflective of practices in ADHD specialty clinics.

The authors concluded, “Further training is needed to improve clinicians’ understanding of ADHD in adulthood and to align diagnostic practices with guideline recommendations. Whereas discrepancies between respondents regarding the relative importance of peripheral symptoms (e.g., memory problems) were most common, a lack of consensus was found even for core symptoms listed by diagnostic criteria. Particularly among psychologists, improved awareness regarding the benefits of stimulant medications is needed to bring their treatment recommendations in line with evidence-based guidelines.”

Brooke C. Schneider, Daniel Schöttle, Birgit Hottenrott, Jürgen Gallinat, and Steffen Moritz, “Assessment of Adult ADHD in Clinical Practice: Four Letters—40 Opinions,” Journal of Attention Disorders (2019) DOI: 10.1177/1087054719879498.