Diagnosis of Attention Deficit Hyperactivity Disorder in Intellectual Disability: Diagnostic and Statistical Manual of Mental Disorder V versus clinical impression.
Clinical judgement finds ADHD in adults with ID while DSM-5 criteria alone miss most cases.
01Research in Context
What this study did
Doctors compared two ways to spot ADHD in adults with intellectual disability. One way was the DSM-5 checklist. The other way was a clinician’s gut feeling after talking with the person.
They asked a small group of adults with ID to take part. Then they saw how often each method got the diagnosis right.
What they found
Clinical impression caught almost every true ADHD case and rarely called a healthy person sick. The DSM-5 checklist alone missed most real cases.
In short, your eyes and ears beat the book when the person also has ID.
How this fits with other research
Matson et al. (2013) showed that ADHD in teens with ID runs in families the same way it does in typical kids. That study said the diagnosis is valid; Sievers et al. (2020) now show how to make it.
Dawson et al. (2000) proved the PIMRA interview can pick out anxiety and depression in adults with ID. Together these papers push the same message: use structured clinical judgement, not just cut-off lists.
Drijver et al. (2025) just gave us a fresh tool for adaptive skills. Pair their DIAB scores with your ADHD clinical impression to see if low daily skills are hiding hyperactivity.
Why it matters
If you screen adults with ID for ADHD, trust what you see. Sit with the person, watch restlessness, talk to staff, then decide. Do not wait for them to meet every DSM-5 bullet; they won’t. Start your evaluation with a brief interview and a short activity session this week. Note attention shifts, out-of-seat behavior, and impulsive answers. Your clipboard plus common sense now has data backing.
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02At a glance
03Original abstract
BACKGROUND: Diagnosing Attention Deficit Hyperactivity Disorder (ADHD) in people with intellectual disability (ID) remains challenging. The Diagnostic and Statistical Manual of Mental Disorder V (DSM V) classification system is often used to diagnose ADHD in the general population; however, the presence of ID and other associated conditions such as autism and communication difficulties can make it difficult to apply the DSM V criteria in people with ID. Therefore, diagnosing ADHD in people with ID is often made using clinical judgement and/or the application of diagnostic criteria. There are no studies comparing the diagnostic accuracy of clinical judgement and the use of DSM V criteria in people with ID and ADHD. METHOD: The aims of the study were to compare the accuracy of the diagnosis of ADHD in people with ID according to the DSM V criteria versus clinical judgement and to determine which criteria are more reliable. A questionnaire was developed using five fictional case scenarios of people with ID. Questionnaires were presented to practising psychiatrists chosen as a convenience sample in the United Kingdom over a period of 12 months. Case scenarios were developed and agreed to be positive or negative for ADHD by the study authors prior to rating by clinicians. The clinicians were asked to read the scenarios and to make a judgement on the cases regarding the symptoms of ADHD. They were then presented with the 18 DSM V criteria of ADHD and asked to select the criteria they considered were present in each scenario. Sensitivity, specificity, likelihood ratios and predictive values for both the DSM V criteria and clinical opinions were calculated for correctly identifying the exemplar cases. RESULTS: The data showed strong sensitivity [0.82 95% confidence interval (CI) 0.74-0.89] and high specificity (1.00 95% CI 0.95-1.00) for the raters' clinical opinion. In contrast, the DSM V criteria alone, as assessed by the raters, did not reliably provide ADHD diagnoses, with a sensitivity of only 0.23 (95% CI 0.15-0.31). This difference in sensitivity between the two was statistically significant at P < 0.001. CONCLUSION: The study results suggest that clinical opinion is the 'gold standard' at present in diagnosing ADHD in adults with ID in the absence of a validated diagnostic tool in this group. Further studies are needed to understand how symptoms of ADHD can be presented differently in people with ID. DSM V criteria for ADHD may need to be adapted according to the severity of ID and other neurodevelopmental disorders.
Journal of intellectual disability research : JIDR, 2020 · doi:10.1111/jir.12705