Community-based tracking and outreach improve childhood vaccination rates

Community-Based Intervention

Public Health Planning

Community-Based Intervention Programs Improve Child Vaccination Rates

Improvements in the rates of childhood vaccinations has, until recently, depended largely on remind/recall strategies employed by provider- and community-based programs (reviewed by Findley, Sanchez, Mejia, Ferreira, Pena, Matos, et al. 2009; Szilagyi, Schaffer, Shone, Barth, Huminston, Sandler et al. 2002). Unfortunately, such programs have failed to erase the racial and economic disparities that leave communities of color more vulnerable to preventable infectious diseases. In an effort to improve the rates of up-to-date child vaccinations in these communities, a group of researchers and clinicians designed and implemented a community program that added tracking and outreach activities to already established programs promoting child vaccination (Northern Manhattan Start Right Coalition; Findley, Irigoyen, Sanchez, Guzman, Mejia, Sajous, et al., 2004). When compared to national averages for all racial groups (74.8%) the improvements were significant, increasing from 65 to 88% for children between the ages of 19 and 35 months during the two-year study period.

Rationale for Further Study

The above study (Findley et al., 2004) suggests focused intervention efforts may have a significant positive effect on vaccination rates for children living in communities of color. What this study failed to show is whether the improved vaccination rates were due specifically to the implemented tracking and outreach efforts, rather than some unknown factors that could have been impacting the community as a whole. In order to provide further validation for their results, the same group of researchers identified a within-community control population that would allow them to draw conclusions about the effectiveness of their program (Findley, Irigoyen, Sanchez, Stockwell, Mejia, Guzman, et al., 2008). Such evidence is currently lacking, especially in comparison to the number of studies that have been published showing the effectiveness of provider-based intervention programs.

Experimental Strategy

Findley et al. (2008) used a retrospective, birth cohort design that examined the vaccination status of children between the ages of 19 and 35 months over a period of 4 years. A total of 10857 immunization records from the New York Citywide Immunization Registry were used, which covered 93.9% of the children which had been enrolled in the Start Right program and 87% of the control group.

The vaccination records provided the outcome measures of whether a child was up-to-date in their 4:3:1:3:3 series of vaccinations (4 diptheria-tetanus-persussis [DTaP]; 3 polio; 1 measles-mumps-rubella; 3 haemophilus influenza b; and 3 hepatitis B), and how big of a lag between the scheduled and actual dates of the last DTaP vaccination in the series (Findley et al., 2008).

Results and Conclusion

Children that were enrolled in Start Right were significantly more likely to be covered by Medicaid and be Latino (p < 0.001), but there was no difference in the mean age. Start Right children were 11% more likely to be immunized (p < 0.001), and after controlling for Medicaid status and ethnicity, were 53% more likely to be up-to-date. Children enrolled in the Start Right program are therefore more likely to be immunized and up-to-date, suggesting a coalition of providers, social and community services, and faith-based organizations, together with tracking and outreach efforts, can significantly improve vaccination rates in communities of color.

An alternative Research Strategy Proposals

The first study the authors conducted used a prospective cohort design (Findley et al., 2004) and the second used a retrospective cohort design (Findley et al., 2008). A potentially more powerful experimental strategy would be to randomize the neighborhoods or communities selected for participation in the Start Right program. For example, neighborhoods or school districts could be matched in terms of ethnicity, income level, Medicaid coverage, and provider density (Fu, Cowan, McLaren, Engstrom, and Teach, 2009), and then selected at random for participation in the Start Right program. The impact of community-wide trends in childhood vaccination rates would be averaged out over multiple neighborhoods or school districts. If necessary, multiple cities could be enrolled to increase the statistical power of the experiment.