Attention Research Update

November 2009

"Helping parents, professionals and educators stay informed about new research on ADHD"

David Rabiner, Ph.D.  Senior Research Scientist, Duke University

           What happens when children's ADHD symptoms are normalized?

Although ADHD is diagnosed based on the presence of inattentive and hyperactive-impulsive symptoms (see for full diagnostic criteria), problems that often co-occur with these symptoms can be larger concerns for parents and teachers.  For example, many children with ADHD have difficulty maintaining positive relations with peers and parents and many struggle with their academic performance.  In fact, difficulties in these areas may be more closely linked to long-term outcomes than core ADHD symptoms themselves.

When core ADHD symptoms improve significantly, what happens to children's functioning in other important areas?  It is tempting to conclude that normalizing inattentive and hyperactive-impulsive symptoms will assure meaningful improvement in important areas.  However, this is not necessarily the case as other difficulties may not have been caused by ADHD symptoms in the first place or may persist even when ADHD symptoms are well-controlled.  Surprising as it may seem, the relationship between normalizing core ADHD symptoms and improvements in other important areas has not been carefully studied.

Because this is such a critical question, I was pleased to recently locate a study that begins to address it [Karpenko et. al., (2009). Clinically significant symptom change in children with ADHD: Does it correspond with reliable improvement in functioning? Journal of Clinical Psychology, 65, 76-93.].  Participants were 417 children from the Multimodal Treatment Study of ADHD (MTA Study), the largest ADHD treatment study ever conducted.  In this study, children were randomly assigned to received either intensive medication management, intensive behavior therapy, a combination of the two, or routine community care.  The children included in the current study were those from one of the first three treatment groups.  You can find a complete summary of the initial MTA Study findings at

These 417 children were grouped according to whether their core symptoms of ADHD and ODD (Oppositional Defiant Disorder) were normalized according to parent and teacher ratings 14 months after treatment began. Children's symptoms were considered 'normalized' when the ratings averaged across all symptoms and across parents and teachers corresponded to their being present either "just a little" or "not at all".  Fifty-five percent (n=231) had ratings that fell in the "normalized" group while 45% (n=186) had ratings that remained elevated. 

Next,the authors computed the percentage of children in the 'normalized' and 'elevated' groups who showed meaningful improvement in several key areas of functioning: parent-child relations, social skills, homework problems, behavior at home, and overall impairment.  These were measured using parent and/or teacher rating scales. Improvement was determined by subtracting the ratings obtained at 14 months from those obtained at baseline.  A statistical formula was then used to determine whether the change on each measure for each child was large enough to be reliable, i.e., unlikely to reflect chance fluctuation.  The authors then compared the percentage of children in "normalized" and "elevated" groups who showed clinically reliable change in each area.

- Results -

Social skills - Based on parent ratings, 66% of children in the normalized group made reliable improvements in social skills compared to 52% of those in the elevated group.  When using teacher ratings, the percentages were 78% and 49% respectively.  In both cases, the difference between the groups was statistically significant.

Homework problems - According to parents' ratings, 66% of 'normalized' children showed reliable reductions in homework problems compared to 45% of children whose symptoms remained elevated.  This difference was significant.

Parent-child relationship - Two dimensions of parent-child relations were examined: power assertion and closeness.  Higher scores on power assertion reflect more problems in the relationship while higher scores on closeness reflect a stronger parent-child bond.  Based on parent ratings, reliable reductions in power assertion was found for 19% of normalized children vs. 15% for the elevated group.  For closeness, the percentages were 21% and 13% respectively.  This latter difference was significant.

Ratings completed by the children themselves yielded non-significant group differences:  17% vs. 13% for closeness and 20% vs. 16% for power assertion.

Overall impairment - Forty-four percent of 'normalized' children compared to 25% of 'elevated' children showed reliable reductions in their overall impairment rating; this difference was statistically significant.

The authors also examined the total number of domains in which reliable improvement was found for each group.  On average, children with normalized symptoms showed reliable improvement on 4 of 9 functional measures.  For children whose symptoms remained elevated,, reliable changed occurred on average in 2 of 9 measures.

- Summary and Implications -

The results of this study are important and informative.  On the one hand, it is clear that when core ADHD symptoms are normalized, children are more likely to show reliable improvements in several important functional areas including social skills, homework, and overall level of impairment.  On the other hand, a substantial percentage of children fail to show meaningful improvement even when their ADHD symptoms have been normalized. Furthermore, improvements in key aspects of parent-child relations were not related to ADHD symptom normalization, although the authors note that this may reflect limitations in the measure of parent-child relations that was used.

These findings highlight the need to move beyond core ADHD symptoms when evaluating children's response to treatment as even the normalization of core symptoms - which often fails to occur - does not guarantee meaningful improvement in key functional areas.  In addition, the fact that many children without normalized symptoms also showed reliable change in key functional outcomes further underscores that ADHD symptom normalization and functional improvement are not tightly linked.  Thus, as emphasized in ADHD treatment guidelines from the American Academy of Pediatrics, the primary goal of ADHD treatment should be to maximize children's functioning rather than simply minimizing core symptoms.

There are several limitations to this study that should be recognized.  First, the authors did not examine how normalization of symptoms was related to children's academic achievement and daily academic success at school, a very important outcome to consider.  Second, children in the 'normalized' group not only had ADHD symptoms normalized but ODD symptoms as well.  Thus, what the results would have been if normalization was based on ADHD symptoms exclusively is not known.  It is reasonable to assume, however, that fewer children would have shown reliable improvement in the areas assessed. Thus, the findings likely overstate the benefits that would accrue from normalizing inattentive and hyperactive-impulsive symptoms exclusively.

It should also be noted that the sample was limited to 7-9-year-old children diagnosed with the combined type of ADHD; these were the youth included in the MTA Study.  How the results would generalize to older children, or to children with the inattentive subtype of ADHD is thus unknown.

These limitations not withstanding, this study addresses an important topic that has not been previously studied.  One hopes that future work by these authors and others will build on this initial examination of how change in core ADHD symptoms relates to children's adjustment in important functional areas as this has important implications for how we think about successfully treating ADHD.

Information presented in Attention Research Update is for informational purposes only, and is not a substitute for professional medical advice.  Although newsletter sponsors offer products and services that I believe will be of interest to subscribers, sponsorship of Attention Research Update does not constitute a specific endorsement or guarantee of any company's product or services.