ABSTRACT
Autism, also referred to as autistic spectrum disorder (ASD) and pervasive developmental disorder (PDD), defines a group of neurodevelopmental disorders affecting approximately 1% of the population which is usually diagnosed in early childhood [1]. Since there are no definitive biological markers of autism for a majority of cases, diagnosis depends on a range of behavioral signs. Experts disagree about the causes and significance of the recent increases in prevalence of ASD [2]. Despite hundreds of studies, it is still not known why autism incidence increased rapidly during the 1990s and is still increasing in the 2000’s [3]. The findings from updated (March 2014) population-based estimates from the Autism and Developmental Monitoring Network Surveillance (ADDM) in multiple U.S. communities, as reported by the Centers of Disease Control and Prevention (CDC), indicates an overall ASD prevalence of 14.7 per 1000 (95% C.I. = 14.3-5.1) or one in 68 children aged 8 years during 2010 [4]. This latest prevalence estimate of ASD as one in 68 children aged 8 years, was 29%
higher than the preceding estimate of one in 88 children or 11.3 per 1000 (95% C.I. = 11.0-11.7) [4].
