Comparison of ICD-10 and Gillberg’s Criteria for Asperger Syndrome

In this study, algorithms designed for the Diagnostic Interview for Social and Communication Disorders (DISCO) were used to compare the ICD-10 criteria for Asperger syndrome with those suggested by Gillberg. Two hundred children and adults were studied, all of whom met the ICD-10 criteria for childhood autism or atypical autism. Only three (1 percent) met criteria for ICD-10 Asperger syndrome. In contrast, 91 (45 percent) met criteria for Asperger syndrome defined by Gillberg, which more closely resemble Asperger’s own descriptions. Results showed that the discrepancy in diagnosis was due to the ICD-10 requirement for ‘normal’ development of cognitive skills, language, curiosity and self-help skills. When comparisons were based on Gillberg’s criteria only, results showed the participants diagnosed as having Asperger syndrome differed significantly from the rest on all but two of Gillberg’s criteria. However, all of these criteria could be found in some of those not diagnosed as having Asperger syndrome. The results emphasize the differences between the two diagnostic systems. They also question the value of defining a separate subgroup and suggest that a dimensional view of the autistic spectrum is more appropriate than a categorical approach.