Table 1.

Immunization Encounter Classification.

	Had immunizations by milestone?
Had provider encounters?	Yes, UTD	Yes, Non-UTD	No
Yes	Immunization Visit	Missed Opportunity	Missed Opportunity
No	—	—	Missed Visit

Where UTD is up to date status for ACIP recommended immunizations in the DTaP, HepB, Hib, Polio, and Varicella series by each milestone age.