Which statement regarding the MMR vaccine is LEAST accurate?

The statement that the MMR (measles, mumps, rubella) vaccine is mandatory for all school-aged children is the least accurate. While many states in the USA require the MMR vaccine for school entry to protect the health of the community and minimize outbreaks, this requirement is not uniform across all states and may be subject to specific exemptions, such as medical or religious exemptions. Therefore, stating that it is mandatory for all school-aged children does not account for these variances in state laws and regulations.

In contrast, the other statements about the MMR vaccine are accurate. The vaccine is indeed administered in two doses, typically the first between 12 to 15 months of age and the second between 4 to 6 years. Additionally, for older children who have not been vaccinated, a single dose can be given to catch up and protect against these diseases, making it accurate. Lastly, immunization between 12 and 15 months is a standard recommendation for initiating the vaccination series, confirming the validity of that statement as well.