title: Identifying birth defects in automated data sources in the Vaccine Safety Datalink.
abstract: OBJECTIVE
  The Vaccine Safety Datalink (VSD), a collaboration between the Centers for Disease Control and Prevention and several large healthcare organizations, aims to monitor safety of vaccines administered in the USA. We present definitions and prevalence estimates for major structural birth defects to be used in studies of maternal vaccine safety.
  
  
  METHODS
  In this observational study, we created and refined algorithms for identifying major structural birth defects from electronic healthcare data, conducted formal chart reviews for severe cardiac defects, and conducted limited chart validation for other defects. We estimated prevalence for selected defects by VSD site and birth year and compared these estimates to those in a US and European surveillance system.
  
  
  RESULTS
  We developed algorithms to enumerate >50 major structural birth defects from standardized administrative and healthcare data based on utilization patterns and expert opinion, applying criteria for number, timing, and setting of diagnoses. Our birth cohort included 497 894 infants across seven sites. The period prevalence for all selected major birth defects in the VSD from 2004 to 2013 was 1.7 per 100 live births. Cardiac defects were most common (65.4 per 10 000 live births), with one-fourth classified as severe, requiring emergent intervention. For most major structural birth defects, prevalence estimates were stable over time and across sites and similar to those reported in other population-based surveillance systems.
  
  
  CONCLUSIONS
  Our algorithms can efficiently identify many major structural birth defects in large healthcare datasets and can be used in studies evaluating the safety of vaccines administered to pregnant women. Copyright © 2017 John Wiley & Sons, Ltd.
authors.affiliation: HealthPartners Institute, Minneapolis, MN, USA.
authors.forename: Elyse Olshen
authors.initials: EO
authors.lastname: Kharbanda
authors.affiliation: HealthPartners Institute, Minneapolis, MN, USA.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Vazquez-Benitez
authors.affiliation: University of Iowa, Iowa City, IA, USA.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Romitti
authors.affiliation: Center for Health Research Kaiser Permanente Northwest, Portland, OR, USA.
authors.forename: Allison L
authors.initials: AL
authors.lastname: Naleway
authors.affiliation: Kaiser Permanente Southern California, Los Angeles, CA, USA.
authors.forename: T Craig
authors.initials: TC
authors.lastname: Cheetham
authors.affiliation: Yale University School of Medicine, New Haven, CT, USA.
authors.forename: Heather S
authors.initials: HS
authors.lastname: Lipkind
authors.affiliation: University of Minnesota, Minneapolis, MN, USA.
authors.forename: Shanthi
authors.initials: S
authors.lastname: Sivanandam
authors.affiliation: Kaiser Permanente Northern California, San Francisco, CA, USA.
authors.forename: Nicola P
authors.initials: NP
authors.lastname: Klein
authors.affiliation: Harvard Pilgrim Health Care Institute and Harvard Medical School, Boston, MA, USA.
authors.forename: Grace M
authors.initials: GM
authors.lastname: Lee
authors.affiliation: Group Health Research Institute, Seattle, WA, USA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Jackson
authors.affiliation: Institute for Health Research, Kaiser Permanente Colorado and Ambulatory Care Services, Denver Health, Denver, CO, USA.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Hambidge
authors.affiliation: HealthPartners Institute, Minneapolis, MN, USA.
authors.forename: Avalow
authors.initials: A
authors.lastname: Olsen
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: Natalie
authors.initials: N
authors.lastname: McCarthy
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, GA, USA.
authors.forename: Frank
authors.initials: F
authors.lastname: DeStefano
authors.affiliation: HealthPartners Institute, Minneapolis, MN, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Nordin
mesh_terms: D000293:Adolescent; D000328:Adult; D016907:Adverse Drug Reaction Reporting Systems; D000465:Algorithms; D000013:Congenital Abnormalities / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D011247:Pregnancy; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D014612:Vaccines / Q000008:administration & dosage / Q000009:adverse effects*; D055815:Young Adult
chemical_list: D014612:Vaccines
keywords: congenital anomalies; electronic health data; pharmacoepidemiology; prevalence; validity