The health survey includes a question about autism or autism-related disorders. This question is part of a series of questions about chronic disorders in children. The series starts with thequestion: 'Would you be so kind as to indicate, whether your child suffers or has suffered from one of the following diseases or disorders during the past 12 months'. Subsequently, more detailed questions are asked about the diseases and disorders. If parents or guardians answeraffirmatively to the question about autism or autism-related disorders, like the Asperger syndrome or PDD-NOS, it is assumed that the child suffers from autism or a disorder related to autism. The health survey is only conducted among private households; the institutional population is not taken into account.
Autism orrelated disorders in treatment programmes refers to the diagnosis registered as the primary diagnosis in one or more consecutive diagnosis treatment combinations (DTCs). It refers to a diagnosis in the category pervasive developmental disorders and includes autism, Rett syndrome, Asperger syndrome, disintegrative disorderandpervasive developmental disordernot otherwise specified (PDD-NOS).