Some of the confusion comes from changes in the international diagnostic criteria over the past few years. In 2013 a new set of diagnostic terms were released as a part of the updated Diagnostic and Statistical Manual - Fifth Edition (DSM-V). Prior to the DSM-V three separate conditions were used to describe children affected by ASD. These were Autistic Disorder, Asperger's Syndrome and Pervasive Developmental Disorder - Not Otherwise Specified (PDD-NOS). With the release of the DSM-V these individual diagnoses have now been merged into one single Autism Spectrum Disorder (ASD) diagnosis.
The new umbrella term of ASD captures the similarities between the different disorders. Essentially children with ASD experience difficulties understanding the emotions of others and how to interact socially. As well as social difficulties, individuals with ASD often find it difficult to be flexible, struggle to cope with changes and have repetitive/obsessive behaviours. Individuals with ASD can also find certain sensory experiences overwhelming and may be quite sensitive to sound, touch, smell or taste.
After a diagnosis of ASD is made a rating system is applied to indicate the level of need for the individual. Professionals provide a severity rating of either 1, 2 or 3. This can be thought of in terms of Mild, Moderate or Severe symptom levels respectively. This rating system helps with understanding the level of support required and what assistance may be available.
ASD is a neurological (brain based) condition meaning it is generally life long. However early intervention by professionals such as Psychologists, Speech Pathologists and Occupational Therapists can assist individuals in gaining improvements in day to day activities and interactions. Generally, the earlier ASD is identified and treated the better the long-term outcomes.