From Reuters:

"In our country, we think the doctor should have all the medical records," said Dr. James McElligott, a pediatrician at the Medical University of South Carolina who worked on the study. "I like the idea of putting the ownership back in Mom's hands and empowering her a little bit."

When parents kept a so-called shot card, their child's odds of being up-to-date on vaccinations rose by more than half.

40 percent of the toddlers had a shot card, and 84 percent of these had up-to-date vaccinations. By contrast, only 79 percent of the children without a card had all their shots.

Use the card: it doesn't have a downside and it's cheap."

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