Comparing autism, PDD-NOS, and other developmental disabilities on parent-reported behavior problems: little evidence for ASD subtype validity.
Old autism subtype labels tell you almost nothing about behavior problems once age and IQ are matched.
01Research in Context
What this study did
The team asked parents to fill out the Child Behavior Checklist.
They compared three groups: kids with Autistic Disorder, kids with PDD-NOS, and kids with other delays.
All kids were matched on age and non-verbal IQ so the groups started equal.
What they found
Only two tiny differences showed up.
Parents of PDD-NOS kids rated two anxiety items slightly higher.
Every other behavior problem looked the same across groups.
How this fits with other research
Amore et al. (2011) adds a twist. They tracked the same labels over time and found PDD-NOS was the least stable diagnosis.
Together these papers say the labels don’t behave well: today they look alike, tomorrow the label may change.
Fusar-Poli et al. (2017) and Bassett-Gunter et al. (2017) echo the theme. They show boys and girls with autism differ far less than people think.
The big picture: small or shifting gaps keep popping up, whether we split by subtype, sex, or time.
Why it matters
Stop treating PDD-NOS and Autistic Disorder as meaningfully different in your behavior plans. Focus on the child’s actual skills and needs, not the old label.
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02At a glance
03Original abstract
Studies on the distinction between Autistic Disorder (AD) and Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) have been inconclusive. This study examined the validity of PDD-NOS by comparing it to AD and other developmental disorders (DD) on parent-reported behavior problems. Fifty-four children with PDD-NOS were individually matched on age and non-verbal IQ to 54 children with AD and 54 children with DD. Groups were compared on select subscales of the Child Behavior Checklist. High rates of psychopathology were observed in both ASD groups. The only difference between PDD-NOS and AD groups was higher scores in the PDD-NOS group on two items measuring Anxiety/Depression. Cognitive functioning may be a more salient variable than subtype when studying psychopathology in individuals with ASDs.
Journal of autism and developmental disorders, 2011 · doi:10.1007/s10803-010-1054-3