Impact of Missed Opportunities to Vaccinate Preschool-Aged Children on Vaccination Coverage Levels—Selected U.S. Sites, 1991-1992

Vaccination coverage levels among 2-year-old children for each of three routinely recommended vaccines--diphtheria and tetanus toxoids and pertussis (DTP), oral poliovirus (OPV), and measles-mumps-rubella (MMR)--are lower than the national Childhood Immunization Initiative (CII) goal of 90% coverage for these vaccines (1.2). During 1991-1992, CDC awarded contracts to four universities (in Philadelphia, Los Angeles, Baltimore, and Rochester, New York) to conduct evaluations to identify causes of undervaccination, characterize and quantify missed opportunities (MOs) to vaccinate, and assess their programmatic importance. The evaluations targeted high-risk racial/ethnic minority children in inner-city settings in the four urban sites. This report summarizes selected findings* from these studies.