Academic difficulties are one of the most important adverse consequences of ADHD, and they frequently contribute to parents’ decision to seek treatment for their child. Whether treatment consistently yields a positive impact on long-term academic success is thus an important issue; however, the answer to this question has been somewhat controversial.
A study published recently in the Journal of Attention Disorders, Long-term outcomes of ADHD: Academic achievement and academic performance, represents the most comprehensive effort to date to identify and synthesize research related to this important question.
The authors began by identifying all studies published between 1980 and 2012 that reported long-term academic outcomes for youth with ADHD; this was defined as at least 2 years beyond an initial baseline assessment. All studies included a comparison group — either a normative comparison sample or youth with ADHD who were not treated — or a comparison measure, e.g., a pre-treatment baseline measure of academic achievement to which subsequent achievement could be compared.
Academic outcomes were categorized as achievement outcomes or performance outcomes. Achievement outcomes refer to results of standardized achievement tests and reflect knowledge that children have acquired. Performance measures address actual performance at school setting, e.g., school grades, years of schooling completed, graduating from high school. etc. Thus, performance outcomes are especially important because they reflect what students actually accomplish in school.
While these different types of academic outcomes are correlated, they are not identical as one could score well on achievement tests and yet earn poor grades for a variety of different reasons.
Two important research questions were addressed:
- How does untreated ADHD affect academic outcomes over the long-term?
- How does treatment and specific types of treatment impact long-term academic outcomes?
The authors identified 176 studies between 1980 and 2012 that reported long-term academic outcomes associated with treated and untreated ADHD. These studies employed different designs and comparison groups, as well as a variety of different academic measures.
It should be noted that few studies were randomized-controlled trials, which is generally considered to be the gold standard for evaluating treatment effects. This is inevitable when examining long-term outcomes, however, as it is almost impossible to sustain random assignment to treatment or a control condition over an extended time period.
To examine the impact of untreated ADHD on academic outcomes, the authors considered studies comparing outcomes for youth with untreated ADHD to those without ADHD. Outcomes were considered ‘poorer’ when results for youth with untreated ADHD were significantly worse; When no significant difference was found, outcomes were considered ‘similar’.
In studies examining the impact of ADHD treatment, outcomes were considered to ‘improve’ when youth treated for ADHD had significantly better outcomes than untreated youth with ADHD. In studies where outcomes were compared to a pre-treatment baseline, improvement was reflected by significant gains relative to the baseline.
Untreated ADHD outcomes: Across all studies and achievement test outcomes, youth with untreated ADHD had significantly lower scores than youth without ADHD for 75% of the outcomes. They were also lower for 79% of the academic performance outcomes.
Does ADHD treatment help? For achievement test scores, treatment was associated with significant improvement with treatment for roughly 80% of the outcomes examined; this compares to only 25% improvement for untreated ADHD.
For academic performance outcomes, e.g., grades, high school graduation, significant improvement was found under 50% of the time. While lower, the corresponding figure for untreated ADHD was only 21%
What is the impact of different types of treatment? For each type of treatment, i.e., pharmacological, non-pharmacological, or combined, improvement was more likely for achievement outcomes than for performance outcomes. Comparing outcomes between treatment types was difficult as few studies provided any direct comparison of treatments. However, youth who received a combination of pharmacologic and non-pharmacologic treatment were more likely to show improvement for both achievement and performance outcomes than youth who received either treatment alone.
Summary and implications:
These results underscore that untreated ADHD is highly likely to compromise children’s long-term academic achievement and academic performance. While this has been known for some time, integrating relevant studies on this issue over the past 30 years highlights the robustness of this conclusion.
More encouraging was the finding that treatment — both pharmacologic and non-pharmacologic — is often associated with significant gains in long-term academic outcomes. This was more likely for achievement test outcomes than for performance outcomes, however. In other words, while children who receive treatment are very likely to ‘learn’ more, this will be less consistently reflected in how they actually perform at school.
It is also noteworthy that combined treatment — also referred to as multimodal treatment — was more likely to result in positive academic outcomes than treatments used in isolation. This suggests that most youth with ADHD will be better served by treatments that integrate drug and non-drug approaches.
There are some limitations to this study that the authors highlight. Efforts to quantify how much treatment helps, and whether this depends on the length and/or quality of treatment received, could not be addressed. Even making general comparisons between broad treatment approaches, i.e., pharmacologic vs. non-pharmacologic, was limited by the relatively small number of studies where this comparison was made. The authors were also unable to disentangle the effects of ADHD on long-term academic outcomes from the other conditions that often accompany ADHD, i.e., comorbidities such as other behavioral and/or emotional disorders.
These concerns notwithstanding, this comprehensive research review provides a firm basis for concluding that treatment improves academic outcomes for youth with ADHD, particularly for academic achievement measures.
– Dr. David Rabiner is a child clinical psychologist and Director of Undergraduate Studies in the Department of Psychology and Neuroscience at Duke University. He publishes the Attention Research Update, an online newsletter that helps parents, professionals, and educators keep up with the latest research on ADHD.
The Study in Context:
- Survey of 2500 families finds what ADHD treatments seem to work/ not work as applied in the real world
- What should come first to treat ADHD in children, behavior therapy or stimulant medication?
- Having ADHD costs $1.1 million in lower lifetime earnings, even when “treated”
- What are cognitive abilities and how to boost them?