Friday, 1 May 2009

Community Questions and Discussion: 10:00-10:30 a.m.

Coffee served in the lobby 8:30 a.m.

Please Note Location Change:
The Seminar will be held in the Semel Institute Auditorium, Room C8-183
(UCLA Campus Map)

All are welcome!

For further information contact Candace Wilkinson at (310) 825-9041.

Abstract

Until a decade ago, best estimate prevalence rates for autism spectrum disorders were 5 per 10,000 for autism and 20 per 10,000 for the broader spectrum. Recent reports have suggested that the prevalence of autism and related spectrum disorders is considerably higher than previously recognised. A number of recent studies have suggested that the rates for the broad autism spectrum may be as high as one percent. Whilst ICD-10 and DSM-IV diagnostic criteria and standard diagnostic instruments have been used in recent prevalence studies, they still allow scope for variation in interpretation and different severity thresholds applied within the same qualitative domains of impairment, resulting in different prevalence rates. Increased recognition, the broadening of the diagnostic concept over time and methodological differences across studies may account for most or all of the apparent increase in prevalence but other explanations cannot be ruled out, including a true rise in incidence.

Case definition is reliant on the behavioural and developmental picture alone and it is not clear that any 'true boundaries' exist with the heterogeneous 'autism spectrum' or between the behaviours seen in individuals who meet criteria for clinical diagnosis and population individual differences in the characteristics included in the autism phenotype. The behavioural phenotype of autism and the broader autism spectrum disorders includes individuals with different ultimate aetiologies, so even when biological or genetic markers are found they will not be present in all individuals with the phenotype. The fact that autism is not a unitary 'disorder' presents a significant challenge to epidemiological, genetic, biological, neurological and psychological research. Notwithstanding these scientific challenges, services in health, education and social care will need to recognise the needs of children with some form of autism who constitute 1% of the child population.