Monitoring the prevalence of severe intellectual disability in children across Europe: feasibility of a common database

AimOur aim was to study the feasibility of creating a framework for monitoring and undertaking collaborative research on intellectual disability at the European level, based on existing databases of children with such disability. MethodThe characteristics of five existing European intellectual disability databases from four countries (Iceland, Latvia, Ireland, and two in France), were discussed on the basis of ideal criteria set by a working group on childhood intellectual disability as part of the Surveillance of Cerebral Palsy in Europe Network (SCPE-NET). Mean prevalence values for severe intellectual disability for the birth years 1990 till 2002 were compared across databases. ResultsMethods of case recruitment and diagnosis differed across databases, but classification of intellectual disability and completeness were similar. Severe intellectual disability (IQ<50) prevalence estimates were significantly (p<0.001) different across databases (south-east France: 3.3 out of 1000; south-west France: 3.0 out of 1000; Latvia: 3.9 out of 1000; Ireland: 5.0 out of 1000; and Iceland 5.1 out of 1000). InterpretationIn spite of differences in diagnosis and case inclusion across databases, the construction of a common database for severe intellectual disability was deemed feasible through harmonization of certain criteria, such as age, and through restriction to those with severe intellectual disability.