The objective of this report was to analyze vaccination data (vaccine types and dates of administration) collected during health screenings conducted in the middle grades of preschool, by the former Departmental Council of South Corsica, whose responsibilities have since been assumed by the Collectivité de Corse. The vaccines analyzed were as follows: diphtheria-tetanus-polio (DTP), pertussis, Haemophilus influenzae type b (Hib), hepatitis B virus (HBV), pneumococcus, meningococcus C, and measles-mumps-rubella (MMR). The aim of this study was to provide a better understanding of departmental vaccination coverage (VC) and its trends over the past few years. VC at 24 months was also compared with data from the 24-month health certificates (CS24). Finally, the age distribution at the various vaccination doses, compared to the recommended ages, was estimated. This analysis showed that the recommended 95% VC targets, aimed at preventing the onset of epidemics, were not met, particularly for the pneumococcal (3 doses) and MMR (1 dose) vaccines, which nevertheless exceeded 90%. With a vaccination coverage of 50%, the vaccine coverage for the meningococcal C vaccine was the lowest among the valences studied. Vaccination coverage rates were stable or increasing. In this study, a comparison between coverage rates derived from the database analysis and those from the CS24 surveys showed that the latter were consistently higher, with the differences appearing to be greater the lower the coverage rate was. Given the decline in CS24 survey responses in recent years, these results raise questions about the representativeness of the CS24 surveys. Finally, even though a slight discrepancy between doses and recommendations does not necessarily have a significant impact on immunization, the analysis of adherence to the various schedules revealed a number of injections administered later than recommended in the vaccination calendar, but also sometimes earlier. The next steps in this work can be broken down into several points. First, at the local level, analyzing the sub-departmental database could help identify potential areas with lower vaccination coverage in order to implement targeted interventions. Furthermore, to confirm the differences in vaccination coverage between this database and the CS24, additional analyses should be considered. These should help investigate the causes of the discrepancies and, in particular, the issue of the representativeness of the CS24, following the decline in reported data. Finally, taking into account not only vaccination coverage in terms of doses but also adherence to the various schedules will very certainly be a key consideration for initiatives aimed at raising awareness among physicians (understanding the effects of delays, ensuring vaccination coverage aligns with the schedules).