Objective: We assessed fragmentation of children's immunization history among providers and parents of children aged 12 to 35 months in four selected underserved areas.
Study design: Area probability cluster sample surveys were conducted in 1997-1998 in northern Manhattan, San Diego, Detroit, and rural Colorado. Surveys consisted of face-to-face interviews with parents followed by record checks with all named immunization providers. We used Advisory Committee on Immunization Practices recommendations to determine up-to-date (UTD) status with vaccinations. The UTD status for each child was determined in four ways: (1) according to the parent-held immunization records, (2) according to the records of the child's most recent provider, (3) according to the records of the child's second most recent provider, and (4) according to provider and parent-reconciled information.
Results: In all four areas, the majority of records of the most recent provider agreed with the reconciled information. However, in all areas, the percentage of children UTD according to provider- and parent-reconciled information was higher than the percentage of children UTD according to information from only the child's most recent provider or from only parent-held immunization records. Across all sites, the percentage of children UTD with the DTP/DTaP vaccine was 2% to 9% lower, according to the most recent provider's information than according to reconciled information. Similar results were seen for other vaccines. The most recent provider not having complete immunization history was significantly associated with not being UTD in New York and having received unnecessary immunizations in San Diego and Detroit.
Conclusion: For most children, although the records of the most recent provider give accurate data for clinical decision making, the immunization histories of some children in these underserved areas are fragmented between providers and parents. This can limit the provider's ability to vaccinate children appropriately.