Objective: The purpose of this study was to compare long-term school outcomes (academic achievement in reading, absenteeism, grade retention, and school dropout) for children with attention-deficit/hyperactivity disorder (AD/HD) versus those without AD/HD.
Methods: Subjects included 370 children with research-identified AD/HD from a 1976-1982 population-based birth cohort (N = 5718) and 740 non-AD/HD control subjects from the same birth cohort, matched by gender and age. All subjects were retrospectively followed from birth until a median age of 18.4 years (AD/HD cases) or 18.3 years (non-AD/HD controls). The complete school record for each subject was reviewed to obtain information on reading achievement (last available California Achievement Test reading score), absenteeism (number/percentage of school days absent at each grade level), grade retention (having to repeat an entire grade in the subsequent school year), and school dropout (failure to graduate from high school).
Results: Median reading achievement scores at age 12.8 years (expressed as a national percentile) were significantly different for AD/HD cases and non-AD/HD controls (45 vs 73). Results were similar for both boys and girls with AD/HD. Median percentage of days absent was statistically significantly higher for children with AD/HD versus those without AD/HD, although the difference was relatively small in absolute number of days absent. Subjects with AD/HD were three times more likely to be retained a grade. Similarly, subjects with AD/HD were 2.7 times more likely to drop out before high school graduation (22.9%) than non-AD/HD controls (10.0%).
Conclusions: The results of this population-based study clearly demonstrate the association between AD/HD and poor long-term school outcomes.