DSM-5 Field Trials Published
Many Questions Remain
November 6, 2012
Today I want to share with you the results of the DSM-5 “field trials” that just published online in the American Journal of Psychiatry. These trials concern the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), scheduled for publication in spring 2013. The new edition includes changes in the criteria used to diagnose autism spectrum disorder (ASD).
The American Psychiatric Association sponsored field trials to test how well the new DSM criteria are working. They addressed two questions: First, can clinicians use the new criteria reliably? In other words, if one clinician arrives at a diagnosis of ASD based on the new criteria, will another clinician independently arrive at the same conclusion? Second, how do the new criteria change the prevalence of ASD? Specifically, if a child received a diagnosis of ASD based on the older DSM-IV criteria, does that child retain a diagnosis of ASD based on the new DSM-5 criteria?
Before sharing the results, let me provide a little background on how the field trial for ASD was conducted. The research took place at two sites: Baystate Medical Center, in Springfield, Mass., and Stanford University, in Palo Alto, Calif. Sixty-four children being seen in the clinics participated in the study to evaluate ASD criteria. All were at least 6 years old, could communicate in English (independently or through a guardian) and had been screened as being at high risk for ASD or one of the other diagnoses being examined in this study. Two independent clinicians performed the diagnostic evaluations for each child, and the evaluations were performed within two weeks of each other.
The analysis found that clinicians using the new criteria were quite reliable, or consistent, in making a diagnosis of ASD. When the first clinician diagnosed a child with ASD, the second clinician was very likely to do so as well.
What about changes in prevalence with the new criteria? The study showed that the large majority of children retained their ASD diagnosis; only a small number of children who previously had an ASD diagnosis based on DSM-IV criteria no longer received an ASD diagnosis using the DSM-5 criteria. Specifically one of the sites had a slightly lower number of children who received a diagnosis of ASD based on DSM-5 compared to DSM-IV (which included autism, PDD and Asperger syndrome).
The children no longer receiving a diagnosis of ASD instead received a diagnosis of “social communication disorder.” This is a new diagnosis under DSM-5. It identifies children who have difficulties in social interaction and communication, but do not exhibit repetitive behaviors. The presence of repetitive behaviors is a requirement for an ASD diagnosis in the DSM-5 system.
Some positive findings emerged from this study, which is the first to report prospectively collected information based on the most recent DSM-5 criteria. Past studies were based on examination of old records and did not evaluate children in person. It appears that the new system can be used reliably by different clinicians and that the new criteria won’t exclude a large number of children who would have previously qualified for an ASD diagnosis.
However, many questions remain. First, this is a relatively small study of school age children from largely Caucasian backgrounds. Adults with autism were not included, so we don’t know how the proposed diagnostic criteria might affect them. We also don’t know how the proposed changes will affect diagnosis of very young children. It will be important to test the new criteria in larger samples of individuals from diverse ethnic backgrounds across the lifespan.
Second, the study was conducted at academic centers rather than out in the community, where the large majority of children are diagnosed. Third, it’s crucial that we gain a better understanding of the impact of the DSM-5 on autism prevalence estimates. Autism Speaks is funding a study with the CDC to better address this issue.
Finally, as these new diagnostic criteria come into use, we need to closely monitor how they affect people in our communities. Are people able to obtain the services they need based on the new criteria? What specific interventions are being recommended for those who are diagnosed with social communication disorder instead of ASD? Would individuals with social communication disorder benefit from interventions designed for children with ASD?
At Autism Speaks, we remain committed to getting answers to these questions and ensuring that all individuals receive the interventions and services they need.
Geraldine Dawson, Ph.D.
Chief Science Officer, Autism Speaks
This letter is part of a series of updates for the community regarding upcoming changes in the criteria used to diagnosis ASD.