The word “pervasive developmental disorder” can be confusing for some people. It’s not a widely used term in daily life and can raise many questions for a child’s development, behavior, and future support needs.
PDD is a general term for a group of developmental disorders that affect the way a child communicates, socially interacts, and behaves with other people.
The term is not used as often today in diagnoses because medical guidelines have been updated; however, many parents will find it in past medical reports, school records, or online information. Therefore, it is helpful to understand what it means and how it is related to autism today.
Understanding Pervasive Developmental Disorder
The term Pervasive developmental disorder was used to describe developmental problems which occurred in multiple areas of a child’s development, particularly:
- Communication skills
- Social interaction
- Behavior and interests
- Learning and daily functioning in some cases.
The term pervasive indicates that more than one aspect of development is affected. It means it affected more than just one skill. A child may have difficulty talking, understanding social cues, playing with other children, or adapting to changes in routine.
PDD is not just one disease. It is more of a “catch-all” diagnosis that encompasses several more specific ones.
Conditions That Were Included Under PDD
Some of the disorders that are a part of pervasive developmental disorder are:
- Autistic disorder
- Asperger’s syndrome
- Childhood disintegrative disorder
- Rett syndrome
- Pervasive developmental disorder – Not Otherwise Specified (PDD-NOS).
A few of these words no longer have the same meanings as they did previously. Today, most of these diagnoses are classified under autism spectrum disorder (ASD), but the syndrome of RETT syndrome is now known to be a distinct genetic disorder.
A term that is still heard by many parents is PDD-NOS. This is used when a child has some characteristics of autism or developmental differences, but does not meet the criteria for a diagnosis of autism at the time.
Why the Term Is Used Less Today?
Throughout the years, knowledge about autism and developmental disabilities has increased. For this reason, the diagnostic system was changed.
The classification of autism-related conditions changed in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013. In the past, autistic disorder and PDD-NOS were listed as separate diagnoses, but under one umbrella, which was referred to as autism spectrum disorder (ASD).
So when someone asks, “What is pervasive developmental disorder?”, the correct answer today is that it is an older word which was once used for the conditions that are now included in autism spectrum disorder.
Common Signs of Pervasive Developmental Disorder
Children diagnosed with PDD typically have developmental delays, behavioral, and social communication difficulties. While the signs vary from child to child, some of the more common signs are:
Delays in Communication
Some children have delays in communicating their needs. It can be through speech or actions. Other children talk, but they are unable to sustain a conversation and read body language and tone.
Difficulty with Social Interaction
A child might not make eye contact, enjoy playing alone, have trouble making friends or grasp social norms such as taking turns or sharing.
Repetitive Behaviors
This can include repeating the same actions, getting very absorbed in routines or taking up interests.
Sensory Sensitivities
Some children are very sensitive to sound, light, texture or changes in their environment.
Developmental Differences
Parents observe that a child isn’t developing certain skills as expected compared to other children their age, especially in communication and social development.
Not all children show the same signs, and the amount of support needed varies greatly.
What Causes Pervasive Developmental Disorder?
The exact cause is still unknown. Recently, there was a belief that PDD was related to brain development, as with autism. There are indications that genes could be a significant factor, and in some cases, other biological and neurological factors may be the cause.
Parents should understand that they are not to blame for developmental disorders. This is not due to their parenting style, poor discipline, or anything the parent did wrong. They are developmental issues.
How It Was Diagnosed?
In the past, the term PDD was used, and generally, a complete developmental evaluation was conducted. A specialist might review:
- Children learn to speak and communicate clearly
- Social skills
- Play behavior
- Repeating behavior
- Learning to adapt to the environment.
- Feedback from parents on their concerns and developmental history.
Teachers and other professionals are more likely to consider whether a child has ASD or another developmental condition, based on the child’s symptoms, if the child exhibits these difficulties today.
Treatment and Support
The type of support that a child receives is generally the same, whether they are diagnosed with PDD in the past or ASD today, supporting them to develop skills that will help them function in their daily life.
Support can include:
- Experience with speech therapy for communication skills
- Occupational therapy for sensory/daily living support.
- A behavioral therapy that incorporates Applied Behavior Analysis (ABA) to help with behavior, learning, and skill development.
- Special education services provided in school.
- Parents’ training and guidance
The type of support is according to the child’s needs. Some children may need support primarily in communication skills, while others may need support in various areas of learning, behavior, or social development.
Final Thoughts
PDD is an older term used to refer to a group of developmental disorders involving communication, social interaction, and behavior. Current understanding is that it is largely known as part of the overall diagnosis of autism spectrum disorder.
When you see it in a report or hear it from an older source, it doesn’t necessarily mean it’s of a different type than autism. In most cases, it is a classification from developmental history. It is not the label that matters; what matters is understanding the child’s needs and ensuring they receive the right support, guidance, and therapies to help them grow and thrive.
