creasing attention to its use, its limitations, and the implications of studies that were conducted through the analysis of its data.
Throughout the first decade of the VSD’s existence, researchers from the NIP and the MCOs participating in the VSD collaborated on studies that used VSD data. During that time, there was no way for an independent external researcher who did not pursue a collaborative relationship with a NIP-affiliated or MCO-affiliated researcher to use the VSD. In 2002, after requests by independent external researchers that VSD data be made available, the NIP announced the creation of the VSD data sharing program (CDC, 2004d). The VSD data sharing program guidelines (CDC, 2002, 2003a, 2004a,b,c) have been revised multiple times since the inception of the program.
Concerns about data sharing were stimulated in part by public concern over a study initiated in 1999 using VSD data. In fall 1999, researchers at the NIP began a screening study using VSD data to investigate whether exposure to thimerosal in vaccines (to which it was added as a preservative) was associated with neurodevelopmental disorders (DeStefano, 2004; Verstraeten et al., 2003a). Some members of the general public have criticized the thimerosal screening study for changes in the original study protocol, changes in eligibility criteria, the selective official release of preliminary findings, and the inclusion of vaccine-manufacturer representatives in a meeting intended to provide external expert review of the study (Bernard, 2004).
The Institute of Medicine Committee on the Review of the National Immunization Program’s Research Procedures and Data Sharing Program was asked to address the following charge:1
(1a) review the design and the implementation to date of the new Vaccine Safety Datalink Data Sharing Program to assess compliance with the current standards of practice for data sharing in the scientific community and (1b) make recommendations to the National Immunization Program and the National Center for Health Statistics for any needed modifications that would facilitate use, ensure appropriate utilization, and protect confidentiality; and (2a) review the iterative approaches to conducting analysis that are characteristics of studies using the complex, automated
After the transfer of some administrative responsibilities for the VSD from the NIP to the National Center for Health Statistics, the charge was modified on August 31, 2004, to include “and the National Center for Health Statistics” in section 1b of the charge. The charge was modified on November 17, 2004, to substitute “preliminary findings” for “preliminary data” in sections 2b and 2c.