Susceptibility of the CAARS-2 Self-Report to Sophisticated Malingering

The Conners Adult ADHD Rating Scales Second Edition (CAARS-2) is a norm-referenced screening measure of ADHD symptoms and associated clinical concerns in adults. Unlike its predecessor, the CAARS-2 features a Negative Impression Index (NII) to detect unrealistically negative ratings or an exaggerated description of problems. Data presented in the CAARS-2 manual indicate that the NII differentiates simulators and adults with genuine ADHD with high accuracy, sensitivity, and specificity.

We attempted to replicate these findings by conducting a simulation study with 222 adults with and without ADHD. Unlike the original studies, however, simulators were provided a plausible reason for feigning ADHD, coached to simulate and warned to avoid detection, and incentivized for credibly feigning.

On average, simulators earned significant elevations on CAARS-2 scales assessing the number and severity of DSM inattentive and hyperactive-impulsive symptoms. Simulators' DSM scores did not differ significantly from those shown by participants with ADHD. The NII demonstrated high specificity (92%) to honest examinees with ADHD, but low sensitivity to simulators (8%). Most simulators were able to earn elevated CAARS-2 scores while avoiding detection. Most simulators were also able to provide credible responses while still earning high ADHD Index Scores (81%) and endorsing significant impairment in at least one functional domain (90%).

Clinicians should continue to corroborate elevated CAARS-2 symptom scores with objective evidence of real-world functional limitations.