• Open Access

Global Prevalence of Autism and Other Pervasive Developmental Disorders


  • From the Department of Psychiatry, Montreal Children's Hospital, Montreal, Canada and Birkbeck, University of London, London, UK (M.E.); Sangath, Goa, India (G.D.); The Korea Institute for Children's Social Development, Seoul, South Korea (Y.-J.K.); Child Study Center, Yale University School of Medicine, New Haven, USA (Y. S.K.); Nelson R Mandela School of Medicine, University of KwaZulu-Natal, South Africa and Mailman School of Public Health, Columbia University, New York, NY, USA (S.K.); Mexican Autism Clinic, Mexico City Mexico (C.M.); Psychology Department, La Universidad del Zulia, Maracaibo, Venezuela (C.M.-N.); Centre for Global Mental Health, London School of Hygiene and Tropical Medicine, London, UK and Sangath Centre, Goa, India (V.P.); Developmental Disorders Program, Mackenzie Presbyterian University, São Paulo, Brazil (C.S.P.); Center for Behavioural Science and School of Medicine, Nankai University, Tianjin, China (C.W.); World Health Organization (M.T.Y.); Department of Psychiatry, Montreal Children's Hospital, Montreal, Canada (E.F.)

Address for correspondence and reprints: Eric Fombonne, Department of Psychiatry, Montreal Children's Hospital, 4018 Ste-Catherine West, Montreal, QC, H3Z 1P2, Canada. E-mail: eric.fombonne@mcgill.ca


We provide a systematic review of epidemiological surveys of autistic disorder and pervasive developmental disorders (PDDs) worldwide. A secondary aim was to consider the possible impact of geographic, cultural/ethnic, and socioeconomic factors on prevalence estimates and on clinical presentation of PDD. Based on the evidence reviewed, the median of prevalence estimates of autism spectrum disorders was 62/10 000. While existing estimates are variable, the evidence reviewed does not support differences in PDD prevalence by geographic region nor of a strong impact of ethnic/cultural or socioeconomic factors. However, power to detect such effects is seriously limited in existing data sets, particularly in low-income countries. While it is clear that prevalence estimates have increased over time and these vary in different neighboring and distant regions, these findings most likely represent broadening of the diagnostic concets, diagnostic switching from other developmental disabilities to PDD, service availability, and awareness of autistic spectrum disorders in both the lay and professional public. The lack of evidence from the majority of the world's population suggests a critical need for further research and capacity building in low- and middle-income countries. Autism Res 2012, 5: 160–179. © 2012 International Society for Autism Research, Wiley Periodicals, Inc.