Conners Continuous Performance Test-3 performance in a sample of veterans assessed for attention-deficit/hyperactivity disorder: evidence of questionable diagnostic utility

Objective The purpose of this study was to examine the usefulness of the Conners Continuous Performance Test-3 (CPT-3) in a veteran sample evaluated for attention-deficit/hyperactivity disorder (ADHD). Method The study used retrospective data from an outpatient ADHD assessment clinic at a Veterans Affairs Health Care System; patients completed a psychological assessment for diagnostic clarity of ADHD. After excluding those with missing or invalid data, deferred or other/unspecified ADHD diagnosis, severe neurological issues, and stimulant use the day of the exam, the final sample was 241: 144 met criteria for ADHD, 61 met criteria for another psychiatric diagnosis, and 36 were categorized as “clinical” controls. Diagnostic accuracy and non-parametric tests were used to examine the CPT-3 Clinical Likelihood Estimate (CLE) and nine primary performance scores with respect to ADHD diagnosis. Results The CLE was not a good indicator of ADHD diagnosis, with an unacceptable AUC of 0.607 predicting ADHD status and 48.6% of those with ADHD identified as having a minimal likelihood of attention deficits. All nine primary CPT-3 scores were worse in those with ADHD than without, but differences were not clinically significant (d = 0.10–0.24). After controlling for psychiatric comorbidity, there were no differences across the ADHD and clinical control groups. Additionally, inattentive and combined presentations did not significantly differ in performance across all nine scores. Conclusions The CPT-3 does not appear to be useful as a diagnostic tool when evaluating veterans for ADHD. There was no distinct ADHD subtype profile of score abnormalities.