Diagnostic labelling of autism spectrum disorders in NSW

To describe the use of diagnostic labels by clinicians for children with autism spectrum disorders (ASD) and calculate the label-specific and overall agreement between diagnostic labels and Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition (DSM-IV) diagnoses provided by the same clinician.

State-wide active surveillance was used to ascertain children newly recognised with one or more DSM-IV criteria for autistic disorder aged 0-15 years (incident cases) in New South Wales (NSW) between July 1999 and December 2000. Clinicians were asked to supply a diagnostic label and then complete DSM-IV criteria for each child reported.

Questionnaires with diagnostic label and DSM-IV criteria were returned for 348 children. The agreement between labels used and diagnosis based on DSM-IV classification system was the highest for autism (97%) and lower for labels of Asperger disorder, pervasive developmental disorder - not otherwise specified or atypical autism (27%). Kappa overall agreement was 0.31. Level of agreement between label and DSM-IV diagnosis was similar for questionnaires completed by multidisciplinary teams, psychiatrists, paediatricians and psychologists working as part of a team.

A lack of agreement between the diagnostic labelling used by clinicians and diagnosis based on DSM-IV criteria indicates a lack of consistency in diagnostic communication that is necessary to provide best clinical care, appropriate services and relevant information to parents and carers.