1 Department of Pediatrics, Division of Developmental Disabilities, 209 University Hospital School, The University of Iowa, Iowa City, Iowa 52242
Readers who were intrigued by the surprisingly general beneficial effects of measles vaccine reported by Holt et al1 may be interested to know that a precedent exists for such a finding. A series of articles by Black, Fox, Elveback, and co-workers2-6 deserve greater attention. In three independent and classic studies, they documented that preschool children with a history of measles infection had lower cognitive test scores than measles-susceptible children. This effect occurred despite use of approximately six covariates for adjustment.