Therapeutic Response to Methylphenidate in ADHD: Role of Child and Observer Gender

This study aims to examine the interaction between the gender of the child and the gender of the observers (teachers, parents) on the therapeutic response (TR) noted with methylphenidate (MPH) in children with ADHD.

Children with ADHD participated in a two week double-blind, randomized, cross-over clinical trial with MPH and placebo, and the difference between the week of treatment with MPH and placebo was calculated for each measure to obtain the treatment response (TR) with MPH. The TR for differences based on the gender of child and the observer was examined by using a univariate analysis of covariance (ANCOVA).

299 children (269-male, 30-female; average age 8.9±1.8 years) were evaluated by 52 male teachers, 212 female teachers; 269 female parents and 30 male parents. For the baseline week, the ANCOVA analysis for teachers yielded a significant teacher's gender x child's gender interaction. For the evaluation of TR, the ANCOVA analysis revealed a significant teacher's gender x child's gender interaction whereas no parent's gender x child's gender interactions were noted, all noted interactions were of a small effect size (eta squared <0.02).

These results suggest that there are differences in symptom assessment between parents and teachers at baseline and with TR based on the gender of the observer and the child. While clinicians need to be aware of these interactions, it remains unclear if these interactions will be clinically useful due to the small effect sizes.