[Strategies to increase and maintain high immunization levels in children]

Various strategies for achieving high immunization rates and better knowledge of immunization status are evaluated. Sixty-nine studies were assessed. Laws requiring documented proof of immunity for all children at the beginning of the school year are associated with a substantial increase in immunization rates, while computerized registries contribute to improved knowledge of immunization status. Research on recall systems, whether parent or provider oriented, produces contradictory evidence. The question of provider motivation as a determinant for achieving high immunization rates remains to be adequately assessed. Laws requiring documented proof of immunity and access to a centralized and efficient immunization registry are key measures for maintaining high immunization levels.