Sensitivity of scales to evaluate change in symptomatology with psychostimulants in different ADHD subtypes

To assess the sensitivity of scales (Conners' Global Index Parent and Teacher form [CGI-P, CGI-T], Clinical Global Impression Scale [CGI], Continuous Performance Test [CPT], and Restricted Academic Situation Scale [RASS]) in evaluating improvement in symptomatology with methylphenidate in different Attention Deficit Hyperactivity Disorder (ADHD) subtypes.

Four hundred and ninety children (309 with ADHD Combined/Hyperactive [ADHD-CH] and 181 with ADHD Inattentive subtype [ADHD-I]) participated in a two week double-blind placebo-controlled crossover methylphenidate trial.

CGI-P showed small effect size for ADHD-I and medium effect size for the ADHD-CH subtype. CGI-T showed medium effect size for ADHD-I and large effect size for ADHD-CH subtype. CGI and RASS showed large effect size while CPT showed medium effect size for both subtypes.

Acute behavioural assessments by clinicians (CGI, RASS) are better at detecting improvement with medication in all subtypes than parent or teacher reports (CGI-P, CGI-T). CGI-T is better than CGI-P for ADHD-I in detecting change in symptomatology as there is a greater demand for attention at school.