The youngest children (bottom third) in fourth grade are 50
percent more likely to be prescribed stimulants for attention-
deficit hyperactivity disorder (ADHD) by seventh grade than the
oldest kids in the class, according to a new study. These
younger students were also almost twice as likely to score low
on math and language arts standardized tests. “Birthday cutoffs
for school entry necessarily lead to an age span of at least 12
months within a classroom,” said the authors. “At age 5, this
span accounts for 20 percent of the child’s age and presents a
difference in maturity and performance between the youngest and
the oldest child in class.” Researchers from the Mount Sinai
School of Medicine reached this conclusion from a population-
based study of children in Iceland. Since the gap seems to
persist through age 14 in the study, “this should be taken into
account when evaluating children’s performance and behavior in
school to prevent unnecessary stimulant treatment,” to make sure
kids aren’t getting a lifel