title: Frequent vaccination missed opportunities at primary care encounters contribute to underimmunization.
abstract: OBJECTIVE
  To examine missed opportunities to administer an eligible vaccination (MOs) and their contribution to underimmunization in contemporary pediatric practices.
  
  
  METHODS
  This study was a retrospective analysis from 42 diverse pediatric practices located throughout the US. Medical records of 50 randomly selected children 3-18 months of age per practice were reviewed in Spring 2013. Immunization status for age and MOs were assessed as of each encounter and as of March 1, 2013.
  
  
  RESULTS
  Of 2076 eligible patients, 72.7% (95% CI 67.6-77.9) were up-to-date with receipt of standard vaccines. Most children (82.4%; 95% CI 78.3-85.9) had at least 1 MO, and 37.8% (95% CI 30.0-46.2) had at least one MO to administer an overdue vaccination. After adjustment, risk of underimmunization was 3.5 times greater for patients who had ever experienced an MO for an overdue vaccination compared with those who had not (adjusted relative risk = 3.5; 95% CI 2.8-4.3). If all age-appropriate vaccinations had been administered at the last recorded encounter, 45.5% (95% CI 36.8-54.5) of the underimmunized patients would have been up to date at the time of assessment.
  
  
  CONCLUSIONS
  MOs were common and contributed substantially to underimmunization in this contemporary sample of diverse primary care practice settings.
authors.affiliation: Goldberg Center for Community Pediatric Health, Children's National Health System, Washington, DC; Center for Translational Science, Children's National Health System, Washington, DC. Electronic address: lfu@childrensnational.org.
authors.forename: Linda Y
authors.initials: LY
authors.lastname: Fu
authors.affiliation: Goldberg Center for Community Pediatric Health, Children's National Health System, Washington, DC.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Zook
authors.affiliation: Goldberg Center for Community Pediatric Health, Children's National Health System, Washington, DC.
authors.forename: Janet
authors.initials: J
authors.lastname: Gingold
authors.affiliation: Center for Translational Science, Children's National Health System, Washington, DC.
authors.forename: Catherine W
authors.initials: CW
authors.lastname: Gillespie
authors.affiliation: Goldberg Center for Community Pediatric Health, Children's National Health System, Washington, DC.
authors.forename: Christine
authors.initials: C
authors.lastname: Briccetti
authors.affiliation: Goldberg Center for Community Pediatric Health, Children's National Health System, Washington, DC; Center for Translational Science, Children's National Health System, Washington, DC.
authors.forename: Denice
authors.initials: D
authors.lastname: Cora-Bramble
authors.affiliation: Betty Irene Moore School of Nursing, University of California Davis, Sacramento, CA.
authors.forename: Jill G
authors.initials: JG
authors.lastname: Joseph
authors.affiliation: Goldberg Center for Community Pediatric Health, Children's National Health System, Washington, DC; Center for Translational Science, Children's National Health System, Washington, DC.
authors.forename: Rachel Y
authors.initials: RY
authors.lastname: Moon
mesh_terms: D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011320:Primary Health Care; D012189:Retrospective Studies; D014611:Vaccination / Q000706:statistics & numerical data*