Attainments of severely mentally retarded adolescents by aetiology.

Piagetian cognitive level, language abilities, adaptive behaviour and graphic skills were assessed in three groups of adolescents with severe learning difficulties: Down's syndrome (DS), congenital cerebral palsy (CP) and unknown origin (NSP). Results were compared with assessments made seven years earlier. A wide range of scores was observed in each group. Medians of the DS and NSP groups were similar and generally were significantly higher than those of the CP group. When the number and severity of other impairments and disabilities (HDCP) was taken into account, group averages of attainments and progress were very similar. Implications for intervention are discussed.