Abstract
BACKGROUND: The present study evaluated two psychometric instruments derived from the objective measurement of adult ADHD using the Quantified Behavior Test Plus. The instruments were examined in ADHD versus a clinical group with overlapping symptoms including borderline personality disorder and bipolar II disorder, and another clinical group with participants assessed for but disconfirmed a diagnosis of ADHD as well as adult normative participants. METHODS: The Quantified Behavior Test Plus includes Continuous Performance Testing and a Motion Tracking System with parameters related to attention and activity operationalized as the cardinal symptoms of ADHD and then summarized into a Weighed Core Symptoms scale with ten cut-points ranging from 0 to 100. A categorical predictor variable called Prediction of ADHD was used to examine the levels of sensitivity and specificity for the Quantified Behavior Test Plus with regard to ADHD. RESULTS: The Weighed Core Symptoms scale separated ADHD and normative participants from each other as well as from the two clinical reference groups. The scale reported highest levels of core symptoms in the ADHD group and the lowest level of core symptoms in the normative group. Analyses with Prediction of ADHD yielded 85 % specificity for the normative group, 87 % sensitivity for the ADHD group, 36 % sensitivity for the bipolar II and borderline group and 41 % sensitivity for the group with a disconfirmed diagnosis of ADHD. CONCLUSIONS: The Weighed Core Symptoms scale facilitated objective assessment of adult ADHD insofar that the ADHD group presented more core symptoms than the other two clinical groups and the normative group. Sensitivity for the Quantified Behavior Test Plus was lower in complex clinical groups with Bipolar II disorder, Borderline disorder and in patients with a disconfirmed diagnosis of ADHD. The psychometric instruments may be further evaluated with regard to well-documented and effective treatment programs for ADHD core symptoms.