Immunisation

The study assesses vaccination status by ever vaccinated, unvaccinated, completion of individual vaccine recommendations, and completion of the overall immunisation schedule. A six-month tolerance period is added to STIKO-recommended age windows because exact birth dates are unavailable and vaccinations may be delayed by illness. Among children with maternal data, 7.7% were born to mothers who had at least one vaccination during pregnancy. Vaccination histories are reconstructed from GePaRD claims data starting at birth. PRECHIC investigates whether prenatal and childhood immunisation influence childhood cancer risk. Among children linkable to maternal claims, maternal vaccinations during pregnancy are assessed as prenatal exposures.