New York, N.Y. (May 9, 2011) – In the first comprehensive study of autism prevalence using a total population sample, an international team of investigators from the U.S., South Korea, and Canada estimated the prevalence of autism spectrum disorders (ASD) in South Korea to be 2.64%, or approximately 1 in 38 children, and concluded that autism prevalence estimates worldwide may increase when this approach is used to identify children with ASD. "Prevalence of Autism Spectrum Disorder in a Total Population Sample," published today online in the American Journal of Psychiatry reports on a study of all children (approximately 55,000) ages 7-12 years in a South Korean community, including those enrolled in special education and the disability registry, as well as all children enrolled in general education schools. Children were systematically assessed using multiple clinical evaluations.
The research by Young Shin Kim, M.D., M.S., M.P.H., Ph.D. of the Yale Child Study Center, and her collaborators Bennett L. Leventhal, M.D., Yun-Joo Koh, Ph.D., Eric Fombonne, M.D., Eugene Laska, Ph.D., Eun-Chung Lim, M.A., Keun-Ah Cheon, M.D., Ph.D., Soo-Jeong Kim, M.D., HyunKyung Lee, M.A., Dong-Ho Song, M.D. and Roy Richard Grinker, Ph.D. found more than two-thirds of ASD cases in the mainstream school population, unrecognized and untreated. "These findings suggest that ASD is under-diagnosed and under-reported and that rigorous screening and comprehensive population studies may be necessary to produce accurate ASD prevalence estimates," stated Autism Speaks Chief Science Officer Geraldine Dawson, Ph.D. "Autism Speaks funded this study to support better detection, assessment and services and to encourage international autism research."
According to Dr. Kim, experts disagree about the causes and significance of reported increases in ASD, partly because of variations in diagnostic criteria and incomplete epidemiologic studies that have limited the establishment of actual population-based rates. "We were able to find more children with ASD and describe the full spectrum of ASD clinical characteristics," said Dr. Kim. "Recent research reveals that part of the increase in reported ASD prevalence appears attributable to factors such as increased public awareness and broadening of diagnostic criteria. This study suggests that better case finding may actually account for an even larger increase. While the current project did not investigate potential risk factors in this particular population, the study does set the stage for ongoing work to examine genetic and environmental factors contributing to the risk of ASD."
This study is further evidence that autism transcends cultural, geographic, and ethnic boundaries and that autism is a major global public health concern, not limited to the Western world. To date, there is no evidence of differences in the way ASD is expressed in children around the world; however it is possible that cultural factors may impact diagnostic practices and prevalence estimates. As a result, the South Korean study took a comprehensive approach to mitigate potential cultural bias. According to Dr. Grinker, a cultural anthropologist at George Washington University, "Parent and teacher focus groups were conducted to identify local beliefs that might influence symptom reporting and to address stigma and misunderstandings related to ASD. Further, clinical diagnoses were established by Korean diagnosticians with extensive clinical and research experience in both the U.S. and Korea and were validated by North American experts."
The study does not suggest that Koreans have more autism than any other population in the world. What it does suggest is that autism is more common than previously thought and that, if researchers look carefully, especially in previously understudied, non-clinical populations, they may find more children with ASD. In addition to the South Korean study, Autism Speaks is supporting similar epidemiological research efforts in India, South Africa, Mexico, and Taiwan, including the translation and adaptation of the gold-standard diagnostic instruments into languages spoken by more than 1.7 billion people worldwide.
"This is the first comprehensive population sample-based prevalence calculation in Korea, and replication in other populations is essential," explained Dr. Dawson. "Notwithstanding the need for replication, this study provides important evidence that the application of validated, reliable and commonly accepted screening procedures and diagnostic criteria applied to a total population has the potential to yield an ASD prevalence exceeding previous estimates."
"We know that the best outcomes for children with ASD come from the earliest possible diagnosis and intervention," concluded Dr. Kim and her colleague Dr. Koh from the Korea Institute for Children's Social Development, "Goyang City, host of the Korea study, has courageously responded to these study findings by providing comprehensive assessment and intervention services for all first graders entering their school system. We hope that others will follow Goyang City's example so that any population based identification of children with ASD is accompanied by intervention services for those children and their families."
This research was funded by a Pilot Research Grant from Autism Speaks as well as grants from the Children's Brain Research Foundation, NIMH and the George Washington University Institute for Ethnographic Research.
About Autism
Autism is a complex neurobiological disorder that inhibits a person's ability to communicate and develop social relationships, and is often accompanied by behavioral challenges. Autism spectrum disorders are diagnosed in one in 110 children in the United States, one in 70 boys. The prevalence of autism has increased 600 percent in the past two decades. The Centers for Disease Control and Prevention have called autism a national public health crisis whose cause and cure remain unknown.
About Autism Speaks
Autism Speaks is the world's largest autism science and advocacy organization. Since its inception in 2005, Autism Speaks has made enormous strides, committing over $160 million to research and developing innovative new resources for families. The organization is dedicated to funding research into the causes, prevention, treatments and a cure for autism; increasing awareness of autism spectrum disorders; and advocating for the needs of individuals with autism and their families. In addition to funding research, Autism Speaks has created resources and programs including the Autism Speaks Autism Treatment Network, Autism Speaks' Autism Genetic Resource Exchange and several other scientific and clinical programs. Notable awareness initiatives include the establishment of the annual United Nations-sanctioned World Autism Awareness Day on April 2, which Autism Speaks celebrates through its Light it Up Blue initiative. Also, Autism Speaks award-winning "Learn the Signs" campaign with the Ad Council has received over $258 million in donated media. Autism Speaks' family resources include the Autism Video Glossary, a 100 Day Kit for newly-diagnosed families, a School Community Tool Kit and a community grant program. Autism Speaks has played a critical role in securing federal legislation to advance the government's response to autism, and has successfully advocated for insurance reform to cover behavioral treatments in 25 states thus far, with bills pending in an additional 13 states. Each year Walk Now for Autism Speaks events are held in more than 80 cities across North America. To learn more about Autism Speaks, please visit www.autismspeaks.org.
About the Co-Founders
Autism Speaks was founded in February 2005 by Suzanne and Bob Wright, the grandparents of a child with autism. Bob Wright is Senior Advisor at Lee Equity Partners and Chairman and CEO of the Palm Beach Civic Association. He served as Vice Chairman of General Electric; and as the Chief Executive Officer of NBC and NBC Universal for more than twenty years. He also serves on the boards of the Polo Ralph Lauren Corporation, Mission Product, LLC, EMI Group Global Ltd. and the New York Presbyterian Hospital. Suzanne Wright is a Trustee Emeritus of Sarah Lawrence College, her alma mater. Suzanne has received numerous awards, the Women of Distinction Award from Palm Beach Atlantic University, the CHILD Magazine Children's Champions Award, Luella Bennack Volunteer Award, Spirit of Achievement award by the Albert Einstein College of Medicine's National Women's Division and The Women of Vision Award from the Weizmann Institute of Science. In 2008, the Wrights were named to the Time 100 Heroes and Pioneers category, a list of the most influential people in the world, for their commitment to global autism advocacy. They have also received numerous awards such as the first ever Double Helix Award for Corporate Leadership, NYU Child Advocacy Award, Castle Connolly National Health Leadership Award and The American Ireland Fund Humanitarian Award. In May of 2010 they received Honorary Doctor of Humane Letters Degrees from St. John's University in Queens and delivered the commencement address as the first married couple to be bestowed such an honor.
Journal
American Journal of Psychiatry