Linking Immunization Information System (IIS) Data to the Oklahoma Pregnancy Risk Assessment Monitoring System (PRAMS)

Background: Immunization Information Systems (IIS) offer enormous potential in identifying vaccine coverage rates of children at a state, regional or community level. Yet most IIS captures little information beyond basic demographics that identify risk factors related to poor coverage. The Centers for Disease Control and Prevention’s (CDC) Pregnancy Risk Assessment Monitoring System (PRAMS) is an ongoing population-based survey of new mothers that identifies maternal and early infancy risk factors. By linking IIS data with PRAMS, a more complete picture of maternal and family influences that impact immunization coverage may be formed.

Setting: Oklahoma State

Population: Pregnancy Risk Assessment Monitoring System (PRAMS) and IIS data

Project Description:Data from the 2005-2006 birth cohorts from Oklahoma State Immunization Information System (OSIIS) and PRAMS were linked to create the analytic dataset. Linkage was performed using the birth certificate numbering system, a common field in both data sets. Previous to the link, OSIIS data were reviewed for potential completeness of immunization records. Data were assessed to determine the overall strength of the linkage as well as to determine if there were significant demographic differences in matched children with complete and incomplete immunization records at age two years. In examining demographic differences, we reviewed mother’s race, marital status, education and ethnicity. Descriptive statistics and a logistic regression were run to determine associations at a significance level of p< .05.  

Results/Lessons Learned: A total of 3,875 PRAMS records and 111,699 OSIIS records were used for the match of the 2005-06 birth cohort. Eighty-four percent (3,250) of PRAMS records were successfully matched to an OSIIS record. Of the 3,250 PRAMS linked records, 2,167, or 66.7 percent of the records were considered to have an up-to-date immunization record. Of the total records matched, no differences in demographic characteristics were found between PRAMS children with complete and incomplete immunization records.