Vaccine Safety Datalink
The Vaccine Safety Datalink Project (VSD) was established in 1990 by the United States Centers for Disease Control and Prevention (CDC) to study the adverse side effects of vaccines.
Four large health maintenance organizations, including Kaiser Permanente, were initially recruited to provide the CDC with medical data on vaccination histories, health outcomes, and subject characteristics.  The VSD database contains data compiled from surveillance on more than seven million Americans, including about 500,000 children from birth through age six years (2% of the U.S. population in this age group).
The VSD data-sharing program is now being administered by the National Center for Health Statistics Research Data Center.  The data sharing guidelines have been revised to include comments from interested groups as well as recommendations from the Institute of Medicine (IOM).
Data from the Vaccine Safety Datalink Project have been utilized to address a number of vaccine safety concerns; examples include a study clarifying the risk of anaphylaxis after vaccine administration and several studies finding no link between thimerosal-containing vaccines and autism.

# Notes
-  Chen RT, Glasser JW, Rhodes PH;  et al. (1997). "Vaccine Safety Datalink project: a new tool for improving vaccine safety monitoring in the United States. The Vaccine Safety Datalink Team". Pediatrics. 99 (6): 76573. PMID 9164767.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link) .mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
-  Bohlke K, Davis RL, Marcy SM;  et al. (2003). "Risk of anaphylaxis after vaccination of children and adolescents". Pediatrics. 112 (4): 81520. PMID 14523172.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
-  Verstraeten T, Davis RL, DeStefano F;  et al. (2003). "Safety of thimerosal-containing vaccines: a two-phased study of computerized health maintenance organization databases". Pediatrics. 112 (5): 103948. PMID 14595043.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
-  Thompson WW, Price C, Goodson B;  et al. (2007). "Early thimerosal exposure and neuropsychological outcomes at 7 to 10 years". N. Engl. J. Med. 357 (13): 128192. doi:10.1056/NEJMoa071434. PMID 17898097.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)