Clinical reports have long described girls with ADHD as better behaved and more teacher-compliant in the classroom than boys with ADHD, and many have speculated that these factors have played an ongoing role in the under-diagnosis of girls with ADHD.

An important new study has carefully documented these different classroom behavior patterns. Abikoff and his colleagues examined 403 boys and 99 girls with combined type ADHD, ages 7-10, in a naturalistic classroom setting, to explore the effects of gender and comorbid conditions upon behavior.

To fully appreciate the importance of these findings, we want to underline that all of the girls in this study met the criteria for both hyperactive/impulsive ADHD, as well as inattentive type, and were therefore categorized as having “combined type.” We emphasize this because even these girls demonstrated few of the behaviors that so often lead to teacher referral. We can safely assume that girls …