Kevin J. Dombkowski, General Pediatrics, Child Health Evaluation and Research Unit, University of Michigan, 300 North Ingalls, Room 6C11, Ann Arbor, MI, USA, Paula M. Lantz, School of Public Health, University of Michigan, and Gary L. Freed, Child Health Evaluation and Research Unit, University of Michigan, 300 North Ingalls Room 627, Ann Arbor, MI, USA.
KEYWORDS:
child, preschool; vaccination; immunization schedule; health surveys, population surveillance
BACKGROUND:
Vaccination status is assessed nationally in terms of up-to-date status without regard to the age at which recommended doses were actually received.
OBJECTIVE:
To assess and contrast rates of age-appropriate vaccination with those based upon up-to-date status.
METHOD:
Retrospective analysis to determine up-to-date and age-appropriate vaccination status for children 25-72 months of age. Five years of pooled data (1992 - 1996) were obtained from the National Health Interview Survey (NHIS) Immunization Supplement for children 25-72 months of age with immunization data based on written records. The outcome measures used were months of vaccination delay relative to age-appropriate vaccination standard as well as up-to-date vaccination status for the DTP4, Polio3, MMR1 doses and 4:3:1 series.
RESULT:
Of the 9,223 eligible children, 80% were up-to-date for the 4:3:1 vaccination series but 48% had experienced delays relative to age-appropriate standards. For the DTP4 dose, 85% were up-to-date, although only 46% had received this dose age-appropriately. Similarly, 90% of children were up-to-date with their Polio3 dose, with 64% receiving this dose age-appropriately; 96% were up-to-date for the MMR1, and 58% received this dose age-appropriately. Age-appropriate DTP4 vaccination increased by 17 percentage points from 1992 - 1996, whereas up-to-date DTP4 status increased by only 6 percent.
CONCLUSION:
Children with up-to-date vaccination status may experience considerable delay relative to age-appropriate vaccination standards. Consequently, vaccination status measures based solely upon up-to-date status tend to understate the degree of underimmunization in a population. National surveillance of age-appropriate vaccination is necessary to identify subpopulations with the greatest prevalence of vaccination delay and to reveal underlying trends that may not be evident through assessments of up-to-date status.
LEARNING OBJECTIVES:
To illustrate how rates of age-appropriate vaccination can substantially vary from rates based upon up-to-date status.
See more of Poster Presentations
See more of The 37th National Immunization Conference
