Comparing Autism Spectrum Disorder and Social Communication Disorder
In a previous post, we explained the new diagnosis of social communication disorder (SCD). This week, we will look at the differences between this new diagnosis and autism.
Differences in Diagnostic Criteria
Social communication disorder, as described in the Diagnostic and Statistical Manual, requires persistent difficulties in both verbal and nonverbal communication. All of the following must be present:
Deficits in social communication (such as greeting and sharing information)
Impairment in ability to change communication to match context or needs of the listener (such as speaking differently in a classroom than on a playground)
Difficulty following rules for conversation and storytelling (such as taking turns in a conversation)
Difficulties understanding what is not explicitly stated (such as not inferences, idioms, humor or metaphors)
These same deficits in communication are seen in the new definition of autism spectrum disorders, however, in ASD there is the additional requirement of restricted, repetitive patterns of behavior, interests or activities. This includes things such as lining up objects, difficulty with change, strict adherence to routines, rigid thinking patterns, a preoccupation with unusual objected or excessive preoccupation with a specific interest and hyper- or hyposensitivities. For a diagnosis of ASD, social communication impairments and the restricted or repetitive behaviors must be present.
However, the definition of ASD specifically states there must be at least two of these present for a diagnosis of ASD. That means, should a child have problems with social communication and have only one repetitive behavior or restricted interest, the diagnosis would be SCD. In order for a child to be diagnosed with SCD, autism must first be ruled out.
Diagnosing Social Communication Disorder
Some experts are concerned that, because SCD is a new diagnosis, identifying it will be difficult.
Helen Tager-Flusberg writes, "We still lack reasonable clinical measures for assessing pragmatic language impairments...Most clinicians are not trained in identifying pragmatic impairments, so the absence of readily accessible assessment instruments means that they don't have the tools with which to make a diagnosis of SCD." 
Some are considering the diagnosis a mild form of autism, similar to Asperger's syndrome. The diagnosis comes when a child or adult exhibits social difficulties similar to those seen in autism but does not exhibit classic autistic behaviors.
Treating Social Communication Disorder
There seems to be confusion as to how SCD should be treated, what types of services are required and if this diagnosis is eligible for services in schools and other situations. As the diagnosis becomes more mainstream and more children are identified, these concerns might resolve themselves. In the meantime, some people worry that children who no longer fit the criteria for ASD and are given a diagnosis of SCD are being left to fend for themselves.
On the other hand, receiving a diagnosis is just the first step in the process. Once a diagnosis is made, whether ASD or SCD, treatments and educational services should be based on the individual, not on the diagnosis. Interventions that are used to help improve communication skills in children with ASD are the same ones that can be used to help children with SCD. The difference is that there is no standard for treatment, that is, there isn't a specific plan parents and medical professionals can follow. Without a standard, it becomes more difficult to measure results.
"DSM-5 Diagnostic Criteria," 2013, AutismSpeaks.org
 "Evidence Weak for Social Communication Disorder," 2013, May 30, Helen Tager-Flusberg, SImons Foundation Autism Research Initiative
"Social Communication Disorders in School-Age Children," Date Unknown, Staff Writer, American Speech-Language-Hearing Association