Formal diagnosis of autism is performed by medical specialists.
The diagnostic criteria for Autism Spectrum Disorders are set out in the Diagnostic and Statistic Manual Forth Edition (DSMIV).
A. Six or more items from (1), (2), and (3), with at least two from (1), and one each from (2) and (3):
B. Delays or abnormal functioning in at least one of the following areas, with onset prior to age 3 years: (1) social interaction, (2) language as used in social communication, or (3) symbolic or imaginative play.
C. The disturbance is not better accounted for by Rett's Disorder or Childhood Disintegrative Disorder.
This category should be used when there is a severe and pervasive impairment in the development of reciprocal social interaction associated with impairment in either verbal or nonverbal communication skills or with the presence of stereotyped behavior, interests, and activities, but the criteria are not met for a specific Pervasive Developmental Disorder, Schizophrenia, Schizotypal Personality Disorder, or Avoidant Personality Disorder. For example, this category includes "atypical autism" - presentations that do not meet the criteria for Autistic Disorder because of late age at onset, atypical symptomatology, or subthreshold symptomatology, or all of these.
There are five possible sub categories of Autism Spectrum Disorder:
Autism is a 'behavioural' diagnosis, that means that there is no simple blood test to determine if a child has autism. Clinicians are looking for a collection of 'skill deficits' which are things that a typically developing individual would do but this child isn't doing for example language delay, immature play relative to peers. Clinicans are also looking for behavioural excesses, which are things a child might do that typically developing peers wouldn't do, for example protracted tantrums, flapping, lining up objects. For a full list of warning signs click here (Link to blue and orange, EARLY SIGNS TABLE on page 5)
Children may rarely be referred for an EEG or MRI in order to rule out other medical conditions, however to date there is no medical test to diagnose autism. Breakthroughs in medical science are looking closely at DNA sequencing to determine if genetics play a part in autism. To read more about this click here (Link to PDF document 'Consensus Statement: Chromosomal Microarray')
Sometimes parents wonder if a child may have been misdiagnosed with autism, especially as so much of the diagnostic process involves answering questions about a child's behaviour and development. There are some disorders which resemble ASDs but are not ASDs taken from the The Autism Sourcebook (2005) by Karen Siff Exkorn:
Pursuing an explanation for a child's developmental delay can be a time consuming, frustrating and expensive exercise. A parent's reaction to finally receiving a diagnosis of autism can range from shock and outrage to relief that they finally have an answer. It most certainly includes a feeling of grief.
The Raising Children Network has video footage of parents speaking about their experience in receiving a diagnosis of autism for their child. Go to: http://raisingchildren.net.au/special_needs/special_needs_videos.html
Parents can receive subsidised support and counselling through various state funded carer bodies. For example Carers NSW http://www.carersnsw.asn.au/
It is important that parents and extended family seek support at this time so that they are best able to embark on a path of early intervention which has been shown to create the best possible outcome for a child with autism.