Vaccine
Volume 30, Issue 43, Pages 6111-6224 (21 September 2012)
http://www.sciencedirect.com/science/journal/0264410X/30/43

Vaccine and Immunization Surveillance in Ontario (VISION) – Using linked health administrative databases to monitor vaccine safety
Review Article
Pages 6115-6120
Kumanan Wilson, Steven Hawken, Jeffrey C. Kwong, Shelley L. Deeks, Natasha S. Crowcroft, Douglas Manuel

Abstract
Vaccine safety surveillance is a critical component of any population-wide vaccination program. In the province of Ontario, Canada we developed a vaccine safety surveillance system utilizing linked health administration databases. VISION (Vaccine and Immunization Surveillance in Ontario) has conducted population based self-controlled case series analyses to evaluate the safety of recommended pediatric vaccines in the general population and in specific subgroups. We present our experiences with developing this system including preliminary findings and challenges. Key methodological observations include: (1) aggregate health services data as an endpoint appears useful (2) graphical description of events following vaccination are valuable and (3) relative incidence ratios are helpful for overcoming the healthy vaccinee effect.