Accurate vaccine product testing and monitoring requires high quality data of large populations. While the sizes of phase III clinical trials have reached an all time high with up to 60,000 subjects, the power to detect most rare and serious AEFI is still too low.

Reliable risk assessment would involve populations of 50-100 million. This can only be achieved and indeed financed as part of post authorisation safety studies utilizing large linked population based databases of exposure ( i.e., vaccine) and outcome (i.e., disease) data.

Due to the current focus on information and computer technology to provide safer and more efficient health care delivery, the amount of electronic medical records and other electronic health care data is increasing exponentially in many countries. Secondary use of data in electronic medical records and registries of vaccinations would allow for rapid assessments of event rates and associations. However many countries are still struggling in setting up the right infrastructure and defining the requirements and standards. In addition, methods for linkage of these databases need to be developed, validated and implemented.

Working Groups are typically comprised of multidisciplinary teams coming from study centers in different countries. These Working Groups build strategies to establish large linked databases.

The establishment of large linked databases follows the "Brighton linkage program". This is a comprehensive approach based on best practices in other domains of data linkage.

We coordinate the VAESCO project building the basis for a European Vaccine Safety Data Link (EVSD) and we are project partners in a pilot study of an envisioned Global Vaccine Safety Data Link.