Dr. Angela Dunn, a researcher out of California, examined the immunization rates of military kids as reported through a National Institute of Science (NIS) data set from 2012. That data showed that about 28 percent of military kids they examined weren't recorded as up to date on vaccines — more than a quarter of their sample of 3,421 military children aged 19 months to 3 years old. Instead of showing that being in a system like Tricare would mean more consistency with vaccines, the study showed that those in the Tricare system are potentially at greater risk.
For more on this issue, see this Spousebuzz post.