Information on Measles, Mumps and Rubella Vaccine in the Copenhagen School Health Records Register

Background: The Copenhagen School Health Record Register (CSHRR) includes health information from school examinations and is now updated with information on measles, mumps and rubella vaccines for the cohorts born from 1977 to 1994.Aim: The aim of this study is to provide a comprehensive description and validation the newly digitised vaccine information in the CSHRR.Methods: We describe the data collection and the newly digitalised information in the CSHRR. We investigate the extent to which the full CSHRR population is representative of Copenhagen and the entire Danish population. Furthermore, we explore how the registry information on vaccination uptake based on reimbursement data matches the vaccine information obtained from CSHRR for the period during which both data are available.Results: The CSHRR population matches closely the complete population of all schoolchildren in Copenhagen, and information on vaccine uptake in CSHRR matches with vaccine registry data for later cohorts. However, a sizable proportion of the immigrant children in the CSHRR have missing information on vaccination. Removing children who have had no additional immunisations enhances data quality.Conclusions: The CSHRR covers a large share of the Danish population and includes detailed vaccine information. By linking the data to other registry data, the updated CSHRR is valuable resource for future research.