Article

The Vaccine Safety Datalink: Immunization research in health maintenance organizations in the USA

National Immunization Program, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
Bulletin of the World Health Organisation (Impact Factor: 5.09). 02/2000; 78(2):186-94.
Source: PubMed

ABSTRACT

The Vaccine Safety Datalink is a collaborative project involving the National Immunization Program of the Centers for Disease Control and Prevention and several large health maintenance organizations in the USA. The project began in 1990 with the primary purpose of rigorously evaluating concerns about the safety of vaccines. Computerized data on vaccination, medical outcome (e.g. outpatient visits, emergency room visits, hospitalizations, and deaths) and covariates (e.g. birth certificates, census data) are prospectively collected and linked under joint protocol at multiple health maintenance organizations for analysis. Approximately 6 million persons (2% of the population of the USA) are now members of health maintenance organizations participating in the Vaccine Safety Datalink, which has proved to be a valuable resource providing important information on a number of vaccine safety issues. The databases and infrastructure created for the Vaccine Safety Datalink have also provided opportunities to address vaccination coverage, cost-effectiveness and other matters connected with immunization as well as matters outside this field.

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    • "The VSD project was created in 1991 by the National Immunization Program of the CDC, and VSD data collection and study methods have been previously described [12] [13] [14] [15] [16]. The project links medical event information, specific vaccine history , and selected demographic information from the computerized databases of several health maintenance organizations (HMOs). "
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    • "A cohort of infants enrolled in the VSD project (updated through the end of 2000) from KPNW, Kaiser Permanente Colorado (KPC), and KPNC were examined using SAS® software. The VSD project was created in 1991 by the National Immunization Program (NIP) of the CDC and VSD methods were previously described [13-15]. The project links medical event information, specific vaccine history, and selected demographic information from the computerized databases of several HMOs. "
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