Rise in autism related to changes in diagnosis, New study suggests

Over the past 10 years the prevalence rates have risen steadily, from one in 150, to one in 110, and now to one in every 88 children. This represents a 78 percent increase in the number of children identified with an autism spectrum disorder (ASD) over the past decade. What are the reasons for this dramatic increase in the prevalence of ASD? A new study suggests that the rise in the number of cases of autism may be related to changes to autism diagnostic criteria.

The criteria for assessing autism has changed over the last 20 years resulting in a broadening of autism diagnoses and the identification of cases that would not have been diagnosed by using older criteria. The current study published online in the Journal of Autism and Developmental Disorders re-examined 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. Clinicians in the original study used DSM-III criteria to assess individuals as “diagnosed autistic” or “diagnosed not autistic.”  After applying current diagnostic criteria from the DSM-IV-TR to records from participants in the two-decades-old study, sixty-four (59 %) of the 108 originally “Diagnosed Not Autistic” met the current ASD case definition, while those who were found to have autism in the 1980s study continued to qualify for the diagnosis using the current criteria. The average IQ estimate in the newly identified group was also significantly lower than in the original group. Current diagnostic criteria applied to participants ascertained in the 1980s identified more cases of autism with intellectual disability. The researchers conclude, “The results of this study demonstrate a significant effect on ASD case status attributable to changing ASD criteria, particularly with regard to individuals with intellectual impairment,” They also comment, “An important caveat, however, is that we were unable to determine whether it was the broadening of the criteria themselves, or the interpretation of the criteria, which lead to this effect.”

The current study supports the theory that the rise in the number of cases of autism may be related to changes in how the disorder is diagnosed. Another aspect of the autism landscape that has changed over the past 20 years is an increase in the awareness of autism among the general public as well as healthcare professionals. While recent findings suggest that at least a portion of the increase in prevalence can be attributed to these factors, they cannot alone explain the dramatic rise in autism prevalence. According to Autism Speaks, genetic vulnerabilities and interaction with environmental factors are likely contributors to the increase in prevalence. 

Miller, J. S., Bilder, D., Coon, H., Pinborough-Zimmerman, J., Jenson, W., Rice, C. E., Fombonne, E., Pingree, C. B., and Ritvo, E., et al. (2012). Autism spectrum disorder reclassified: A second look at the 1980s Utah/UCLA Autism Epidemiologic Study. Journal of Autism and Developmental Disorders. DOI: 10.1007/s10803-012-1566-0

Lee A. Wilkinson, PhD, CCBT, NCSP is author of the award-winning book, A Best Practice Guide to Assessment and Intervention for Autism and Asperger Syndrome in Schools, published by Jessica Kingsley Publishers

Special Needs Students Bullied More Than Others

Students with special needs continue to face a number of challenges in our nations’ schools and communities. A study published in the Journal of School Psychology found that students receiving special education services for behavioral disorders and those with more noticeable disabilities are not only more likely to be bullied than their general education peers, but are more likely to engage in bullying behavior themselves. Participants in the study were 816 students, 9 to 16 years of age, from nine Midwestern elementary and middle schools in one school district. From this total group, 686 were not receiving special education services (categorized as “no disability”), and 130 were receiving special education services (categorized as “observable disability,” “non-observable disability,” and “behavioral disability”). Data on students’ involvement in bullying, office referrals, and prosocial behavior were collected. Self-report measures were used to assess students’ experiences with bullying and victimization and how often students engaged in various aggressive and prosocial behaviors.

The results indicated that students with behavioral disorders reported the highest levels of bullying others and being bullied themselves. The study also found that students with observable disabilities (e.g.., language impairments, hearing impairments, and mild mentally handicapped) were more likely to bully others and to be victimized compared with students in general education.  As the authors comment, “The observable nature of the disability makes it easy to identify those students as individuals with disabilities, which may place them at a greater risk for being the easy target of bullying. Being frustrated with the experience of victimization, those students might engage in bullying behavior as a form of revenge.”

The study also found that students with non-observable disabilities, such as a learning disability, reported similar levels of bullying and victimization as students without disabilities. They also reported significantly less victimization compared with students with more outward behavioral disabilities. While both boys and girls engaged in bullying, there was no significant gender difference in both general education and special education students when it came to the behavior. Although fifth grade students in general education reported much more victimization than sixth-, seventh-, eighth- and ninth-graders, there was no difference for students in special education.

What are the implications of this study? The authors offer several suggestions for school-based bullying prevention and intervention programming. For example, anti-bullying interventions emphasizing prosocial skills should be implemented for students, regardless of their ability. Students in general education could help the process by serving as prosocial role models for students with disabilities. Teachers may also provide reinforcement for prosocial behavior or assign students in general education with students in special education in small groups to work on class projects together to promote positive interaction. For students with both behavioral and observable disabilities, providing support and teaching strategies to cope with peer victimization are important. Helping students with observable disabilities become better integrated into general education classes may help prevent them from being bullied. "Programming should be consistently implemented across general and special education, should occur in each grade and should be part of an inclusive curriculum," the authors recommend. "A culture of respect, tolerance and acceptance is our only hope for reducing bullying among all school-aged youth."

Swearer, S., Wang, C., Maag, J. W., Siebecker, A. B., & Frerichs, L. J. (2012). Understanding the bullying dynamic among students in special and general education. Journal of School Psychology, 50, 503–520

Lee A. Wilkinson, PhD, CCBT, NCSP is author of the award-winning book, A Best Practice Guide to Assessment and Intervention for Autism and Asperger Syndrome in Schools, published by Jessica Kingsley Publishers. He is also the editor of a volume in the APA School Psychology Book Series, Autism Spectrum Disorder in Children and Adolescents: Evidence-Based Assessment and Intervention in Schools and author of the new book, Overcoming Anxiety and Depression on the Autism Spectrum: A Self-Help Guide Using CBT.