ADHD is far more prevalent among persons with AUD (roughly 20 percent) than it is in the general population. The most accurate way of identifying ADHD is through structured clinical interviews. Given that this is not feasible in routine clinical settings, ADHD self-report scales offer a less reliable but much less resource-intensive alternative. Could the latter be calibrated in a way that would yield diagnoses that better correspond with the former?
A German team compared the outcomes of both methods on 404 adults undergoing residential treatment for AUD. All were abstinent while undergoing evaluations. First, to obtain reliable ADHD diagnoses, each underwent the Diagnostic Interview for ADHD in Adults, DIVA. If DIVA indicated probable ADHD, two expert clinicians conducted successive follow-up interviews. ADHD was only diagnosed when both experts concurred with the DIVA outcome.
Participants were then asked to use two adult ADHD self-report scales, the six-item Adult ADHD Self Report Scale v1.1 (ASRS) and the 30-item Conners’ Adult ADHD Rating Scale (CAARS-S-SR). The outcomes were then compared with the expert interview diagnoses.
Using established cut-off values for the ASRS, less than two-thirds of patients known to have ADHD were scored as having ADHD by the test. In other words, there was a very high rate of false negatives. Lowering the cut-off to a sum score ≥ 11 resulted in correct diagnosis of more than seven out of eight. But the rate of false positives soared to almost two in five. Similarly, the CAARS-S-SR had its greatest sensitivity (ability to accurately identify those with ADHD) at the lowest threshold of ≥ 60, but at a similarly high cost in false positives (more than a third).
The authors found it was impossible to come anywhere near the precision of the expert clinical interviews. Nevertheless, they judged the best compromise to be to use the lowest thresholds on both tests, and then require positive determinations from both. That led to successfully diagnosing more than three out of four individuals known to have ADHD, with a false positive rate of just over one in five.
Using this combination of the two self-reporting questionnaires with lower thresholds, they suggest, could substantially reduce the under-diagnosis of ADHD in alcohol dependent patients.
Mathias Luderer, Nurcihan Kaplan-Wickel, Agnes Richter, Iris Reinhard, Falk Kiefer, Tillmann Weber, “Screening for adult attention-deficit/hyperactivity disorder in alcohol dependent patients: Underreporting of ADHD symptoms in self-report scales,” Drug and Alcohol Dependence (2019), 195:52-58.