The comorbidity of Pervasive Developmental Disorder and Attention Deficit Hyperactivity Disorder: results of a retrospective chart review.
Roughly half of kids with PDD also meet ADHD criteria, so always screen for attention problems.
01Research in Context
What this study did
Goldstein et al. (2004) pulled 27 medical charts of children already diagnosed with Pervasive Developmental Disorder. They checked how many also met DSM-IV rules for ADHD. They used the same clinic notes teachers and parents had given before.
What they found
About half of the kids with PDD also fit ADHD criteria. Twenty-six percent lined up with ADHD-combined type and 33 % with inattentive type. Daily-life trouble scores were no worse for the kids who had both labels, but the group was tiny.
How this fits with other research
Casseus et al. (2024) later looked at 1,145 kids with cerebral palsy and found only 18 % had ADHD, far below the 59 % seen here. The giant sample size makes their lower rate more reliable, so the high PDD-ADHD overlap in Sam et al. may be closer to the real picture for autism.
Harstad et al. (2026) followed five- to seven-year-olds and showed that even children who lose their autism label still end up with ADHD services. Their work stretches Sam’s finding past toddler age, telling us the double diagnosis can appear later.
Niklasson et al. (2009) saw a similar 44 % ASD/ADHD overlap inside 22q11 deletion syndrome. The pattern across studies hints that wherever neurodevelopmental genes are involved, ADHD rides along about half the time.
Why it matters
If you assess a child for autism, add an ADHD screener even when the primary label is PDD. Attention trouble can hide under social or repetitive symptoms, and it may not show in daily impairment right away. Pick a parent checklist like the Vanderbilt and track scores across visits. Early spotting lets you fold attention strategies—clear one-step instructions, visual timers, frequent breaks—into the ABA plan before problem behavior snowballs.
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02At a glance
03Original abstract
OBJECTIVE: To determine if a sample of children meeting diagnostic criteria for a Pervasive Developmental Disorder (PDD) display symptoms and impairment related to Attention Deficit Hyperactivity Disorder (ADHD) sufficient to warrant a comorbid diagnosis of ADHD. Further, do children with PDD displaying such symptoms demonstrate more impairment in daily life activities than those children only having PDD? METHOD: A retrospective chart review was conducted on children (N = 57) diagnosed with the PDD's of Autism or PDD-Not Otherwise Specified (PDD-NOS), or ADHD. Comparative analysis of questionnaire and neuropsychological test data was completed to determine the severity of ADHD-like symptoms presenting among children with PDD. RESULTS: From the pool of subjects having PDD with sufficient data (N = 27), 7 or 26% met DSM-IV criteria for the combined type of ADHD. Nine or 33% met diagnostic criteria for the Inattentive Type of ADHD and 11 or 41% did not demonstrate a significant number of ADHD symptoms to warrant a comorbid diagnosis of ADHD. Results indicate that a subgroup of children with PDD displaying significant ADHD-like symptoms may in fact have ADHD thus warranting a comorbid diagnosis of ADHD. Current data did not suggest children with PDD and the combined type of ADHD demonstrated significantly more impairment in daily life functioning than those children only having PDD. However, this appeared likely the result of small sample size. The data, however, does indicate such children experience more difficulties in daily situations as rated by parents and teachers. CONCLUSION: These findings reinforce clinical observations indicating that some children with PDD may also experience an independent comorbid condition of ADHD, suggesting that a comorbid diagnosis of ADHD with PDD be considered in such cases. If further findings are replicated, the current exclusionary DSM-IV-TR criteria of making such a comorbid diagnosis should be re-considered.
Journal of autism and developmental disorders, 2004 · doi:10.1023/b:jadd.0000029554.46570.68