Developing the Evidence for Public Health Systems to Battle Vaccine Preventable Disease at the Local Level: Data Challenges and Strategies for Advancing Research.

CONTEXT

Generally decreasing local health department (LHD) resources devoted to immunization programs and changes in LHD roles in immunization services represent major shifts in a core LHD service.

OBJECTIVE

Within a rapidly changing immunization landscape and emerging vaccine preventable disease outbreaks, our objective was to examine how LHD immunization expenditures are related to county-level immunization coverage and pertussis rates.

DESIGN

We used a practice-based approach in which we collaborated with practice partners and uniquely detailed LHD immunization expenditure data. Our analyses modeled the ecologic relationship between LHD immunization expenditures and LHD system performance and health outcomes.

SETTING

This study was launched through a consortium of public health Practice-Based Research Network states as part of a suite of studies examining the relationship between various LHD service-related expenditures and health outcomes.

PARTICIPANTS

We investigated and sought to include all LHDs in the states of Florida, New York (except New York City's LHD), and Washington.

OUTCOME MEASURES

With LHD immunization expenditures as our independent variable, our outcomes were 1 year of jurisdiction-level rates of toddler immunization completeness, to measure immunization system performance, and 11 years of annual jurisdiction-level numbers of pertussis cases per 100 000 population, to measure related health outcomes.

RESULTS

Immunization completeness and pertussis rates varied greatly, but our models did not produce significant results despite numerous analytic approaches and while controlling for other factors.

CONCLUSION

While our study was part of a suite of studies using similar methods and producing significant results, this study was instead challenged by serious data limitations and highlighted the gap in consistent, standardized data that can support critically needed evidence regarding immunization rates and disease. With LHDs at the epicenter of reducing vaccine preventable disease, it is vital to utilize emerging opportunities to understand the nature of their efforts in immunization coverage and disease prevention.