210 – Contributed Poster Presentations: Survey Research Methods Section
Estimating County-Level Vaccination Coverage Using Small Area Estimation with the National Immunization Survey-Child
Zachary H. Seeskin
NORC at the University of Chicago
The National Immunization Survey-Child (NIS-Child) is a random digit dialing survey of parents and guardians of children age 19 to 35 months in the United States. The NIS-Child produces annual childhood vaccination coverage estimates at the national and state levels, as well as for select local areas and territories. We describe small area estimation methods using NIS-Child data to generate county-level vaccination coverage rates. Estimates for children by age two years are derived for children born 2007 through 2011 and 2012 through 2016 using 2008-2018 NIS-Child data, combining cohorts to increase sample size. The models use county-level predictors from the Area Health Resource File, Census Planning Database, natality birth records, and other sources. We describe our approach applying cross-sectional Lindley and Smith area-level models (also known as Fay-Herriot models), as well as our methods for selecting county-level predictors of vaccination coverage and limitations associated with these methods. County-level estimates are generated using the James-Stein approach, an empirical best linear unbiased prediction method. Further, we discuss an interactive mapping tool showing how the county-level vaccination coverage estimates vary across counties and how county-level coverage may be associated with county-level characteristics.