Recent worldwide epidemiological surveys of autism conducted in 37 countries are reviewed; the median prevalence of autism is 0.97% in 26 high-income countries. Methodological advances and remaining challenges in designing and executing surveys are discussed, including the effects on prevalence of variable case definitions and nosography, of…

The prevalence of autism spectrum disorders has been steadily rising. In most parts of the world, rates as high as 1% are reported, including in the United States. In Israel, previously reported prevalence rates have been in the 0.2% range, and were based on parental reporting of diagnosis. In this study, records from one of the largest Israeli…

There are no epidemiological data on autism for Mexico. This study was conducted to generate a first estimate of ASD prevalence in Mexico. We surveyed children age eight in Leon (Guanajuato). The sample was stratified in two strata: (1) children having special education and medical records (SEMR; N = 432) and (2) children attending regular schools…

The purpose of the present study was to re-examine diagnostic data from a state-wide autism prevalence study (n = 489) conducted in the 1980s to investigate the impact of broader diagnostic criteria on autism spectrum disorder (ASD) case status. Sixty-four (59%) of the 108 originally "Diagnosed Not Autistic" met the current ASD case definition.…

This study examined changes in the administrative prevalence of autism spectrum disorders (ASD) in Utah children from 2002 to 2008 by record source (school and health), age (four, six, and eight), and special education classification. Prevalence increased 100% with 1 in 77 children aged eight identified with ASD by 2008. Across study years and age…

Autism Spectrum Disorders (ASDs) and childhood obesity (OBY) are rising public health concerns. This study aimed to evaluate the prevalence of overweight (OWT) and OBY in a sample of 376 Oregon children with ASD, and to assess correlates of OWT and OBY in this sample. We used descriptive statistics, bivariate, and focused multivariate analyses to…

This pilot study presents preliminary results concerning the prevalence of Pervasive Developmental Disorder (PDD) in South America. It was a three-phase study conducted in a typical town in Southeast Brazil. Case definition was based in a combination of standardized instruments and clinical evaluations by experts. The prevalence of PDD was…

Analysis of data from 126 children with autism found macrocephaly (head circumstance microcephaly (head circumference <3rd centile) was found in 15.1%. Microcephaly was significantly associated with the presence of medical disorders. (Author/DB)

A review of 32 epidemiological surveys of autism and pervasive developmental disorders found four surveys yielded estimates for childhood disintegrative disorder (CDD) ranging from 1.1 to 6.4 per 100,000. It is concluded that CDD is very rare and its prevalence is 60 times less than that of autistic disorder. (Contains references.) (Author/CR)

This article reviews epidemiological studies of autism and related disorders. Study designs and sample characteristics are summarized. Currently, conservative prevalence estimates are: 13/10000 for autistic disorder, 21/10000 for pervasive developmental disorders not otherwise specified, 2.6/10000 for Asperger disorder, and 2/100000 for childhood…

This article reviews 32 epidemiological studies of pervasive developmental disorders (PDDs) published between 1966-2001. The design and sample characteristics of the surveys are described. Surveys have suggested that the rate for all forms of PDDs are around 30/10,000, but more recent surveys suggest it might be as high as 60/10,000. (Contains…

Factors associated with suicidal ideas, attempts, or threats were studied in adolescent psychiatric outpatients (N=5,426). Multivariate logistic regression analyses were performed by sex on data from 1968-1991. Substance abuse, depression, and disturbed relationships with adults were predictors for both sexes. In girls, antisocial behavior and…