[Genetic mental retardation in the district of Banská Bystrica].

The authors investigated the prevalence of mental retardation (MR) in 6-14-year-old children in the district of Banská Bystrica. The aim was to assess the prevalence of MR and the ratio and character of genetic factors participation in its genesis. The group was based on the Uniform records of defective children and health records of children from special schools and social care institutes in 1987.