Minor malformations, hyperactivity, and learning disabilities.

Standardized minor malformation scores have been reported to predict and identify children with attentional problems and hyperactivity. The reason why this marker works for only a subset of children with attention deficit hyperactivity disorder remains unclear. The dysmorphology scores on all children presenting for a multidisciplinary team evaluation of developmental disorders were examined for diagnostic correlations after children with chromosomal disorders and recognized dysmorphic syndromes were excluded. For 1233 subjects, the mean minor malformation score was 2.94 (SD = 2.05). A significant association between minor malformation scores and IQ (mean = 80.95, SD = 23.67) was accounted for by the group with IQs greater than 100 exhibiting the higher dysmorphology scores. An analysis of variance revealed no significant association between minor malformation scores and hyperactivity or attention deficit disorder. Indeed, the presence of an attention deficit disorder yielded lower mean dysmorphology scores. When the minor malformation scores were compared for those subgroups of children with and without specific learning disabilities, the learning-disabled subjects had significantly higher dysmorphology scores. Minor dysmorphic features do not relate to the presence or absence of attentional problems or hyperactivity in referred children. Rather they appear to characterize that subpopulation of children with attention deficit disorder and learning disabilities as well as a group of learning-disabled children without attentional disorders.