The epidemiology of autistic spectrum disorders: is the
Wing L, Potter D.
Centre for Social and Communication Disorders, Elliot House, Bromley, Kent,
United Kingdom. email@example.com
For decades after Kanner's original paper on the subject was published in
1943, autism was generally considered to be a rare condition with a prevalence
of around 2-4 per 10,000 children. Then, studies carried out in the late 1990s
and the present century reported annual rises in incidence of autism in
pre-school children, based on age of diagnosis, and increases in the
age-specific prevalence rates in children.
Prevalence rates of up to 60 per
10,000 for autism and even more for the whole autistic spectrum were reported.
Reasons for these increases are discussed. They include changes in diagnostic
criteria, development of the concept of the wide autistic spectrum, different
methods used in studies, growing awareness and knowledge among parents and
professional workers and the development of specialist services, as well as
the possibility of a true increase in numbers. Various environmental causes
for a genuine rise in incidence have been suggested, including the triple
vaccine for measles, mumps and rubella (MMR]. Not one of the possible
environmental causes, including MMR, has been confirmed by independent
scientific investigation, whereas there is strong evidence that complex
genetic factors play a major role in etiology. The evidence suggests that the
majority, if not all, of the reported rise in incidence and prevalence is due
to changes in diagnostic criteria and increasing awareness and recognition of
autistic spectrum disorders. Whether there is also a genuine rise in incidence
remains an open question. Copyright 2002 Wiley-Liss, Inc.
60 per 10,000 translates to 1/167. - SM
PMID: 12216059 [PubMed - indexed for MEDLINE]