Minimum time interval adjustment for 4-3-1 immunization rates among two-year-old children

• Published in: American journal of preventive medicine Vol. 16; no. 3; pp. 189 - 194
• Main Authors: Steiner, R.Prasaad, Hughes, Judith A, Richardson, Terry L, Looney, Stephen W, Clover, Richard D, Rowe, Melinda G
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01-04-1999
• Subjects: Child, Preschool; community; Data Collection; Diphtheria-Tetanus-Pertussis Vaccine - administration & dosage; Evaluation Studies as Topic; Female; health status; Humans; immunization; Immunization Schedule; Kentucky; Male; Measles Vaccine - administration & dosage; Measles-Mumps-Rubella Vaccine; Mumps Vaccine - administration & dosage; pediatrics; Poliovirus Vaccine, Oral - administration & dosage; preventive medicine; Retrospective Studies; Rubella Vaccine - administration & dosage; Sampling Studies; Sensitivity and Specificity; Time Factors; Vaccination - statistics & numerical data; vaccine (specific name); Vaccines, Combined - administration & dosage; Kentucky; health status; community; immunization; vaccine (specific name); pediatrics; preventive medicine
• ISSN: 0749-3797; 1873-2607
• DOI: 10.1016/S0749-3797(98)00095-6

Background: The purpose is to determine the administrative validity of the 4-3-1 immunization rates for DPT-OPV-MMR vaccines for 2-year-old children in a community health status assessment project by accounting for premature administration of specific vaccine doses according to ACIP recommended minimal timing intervals.
Methods: A retrospective survey of immunization certificates was made on a random sample of 1,059 kindergarten enrollees in the county, including public, private, and parochial schools. The immunization rates by the crude 4-3-1 counting method were compared with the same method adjusted for minimal time interval vaccine dosing.
Results: By the crude 4-3-1 counting method, 55.5% of the students had complete immunizations by their second birthdate, and 11.8% did not meet the minimum interval recommendations on at least one of 4-3-1 vaccine series. The adjustment for minimum time interval reduced the percent in compliance with the 4-3-1 counting method by age 2 in the community to 50.7%.
Conclusion: The premature timing of vaccine doses is a threat to the validity of the 4-3-1 counting method. The crude 4-3-1 method over-estimates the completed immunization rates for 2-year-olds in this community-based study by about 4.8%.