Immunization Coverage Levels Among 19- to 35-Month-Old Children in 4 Diverse, Medically Underserved Areas of the United States

Preschoolers in these medically underserved areas were not at uniform risk for underimmunization. Because they were designated as health professional shortage areas, the 4 sites in this study were expected to have low immunization-coverage rates. However, this was not the case. In fact, coverage in 3 of the 4 areas was quite high compared with US national figures (73%); only Detroit had a much lower UTD rate (66%). Efforts are needed to improve methods to identify areas with low immunization coverage so that resources can be directed to places where interventions are needed. Our results reveal that an area's need for childhood immunization interventions is not well predicted by a low number of providers per capita. Other criteria must be developed to predict areas or populations with low immunization coverage. Understanding more about the characteristics of children/provider pairs for children who are UTD at 3 months and more about the role of parental hand-held cards, along with finding strategies to improve immunization delivery by providers in Vaccines for Children Program facilities, suggest potentially productive avenues for increasing and sustaining high coverage levels.