Many parents worry about their children getting a large number of vaccinations at the same time. Researchers from the University of Louisville School of Medicine in Kentucky looked into this issue in a study of 1,000 children, all of whom were under 13. The children were divided into three groups according to whether they had got their vaccinations on time (all within their first year of life), had had them later or had only had certain vaccinations. The children took IQ, memory, attention and language tests and the researchers found no differences between the groups.
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