Matthew F Daley1, Jason M Glanz2, Sophia R Newcomer3, Michael L Jackson4, Holly C Groom5, Marlene M Lugg6, Huong Q McLean7, Nicola P Klein8, Eric S Weintraub9, Michael M McNeil10. 1. Institute for Health Research, Kaiser Permanente Colorado, Denver, CO, United States; Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, United States. Electronic address: matthew.f.daley@kp.org. 2. Institute for Health Research, Kaiser Permanente Colorado, Denver, CO, United States. Electronic address: jason.m.glanz@kp.org. 3. Institute for Health Research, Kaiser Permanente Colorado, Denver, CO, United States. Electronic address: sophia.r.newcomer@kp.org. 4. Group Health Research Institute, Seattle, WA, United States. Electronic address: jackson.ml@ghc.org. 5. Kaiser Permanente Northwest, Portland, OR, United States. Electronic address: holly.c.groom@kpchr.org. 6. Kaiser Permanente Southern California, Pasadena, CA, United States. Electronic address: marlene.m.lugg@kp.org. 7. Marshfield Clinic Research Foundation, Marshfield, WI, United States. Electronic address: mclean.huong@marshfieldclinic.org. 8. Kaiser Permanente Northern California, Oakland, CA, United States. Electronic address: nicola.klein@kp.org. 9. Immunization Safety Office, Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States. Electronic address: eiw8@cdc.gov. 10. Immunization Safety Office, Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, United States. Electronic address: mmm2@cdc.gov.
Abstract
BACKGROUND: To address public concern about the safety of the childhood immunization schedule, the Institute of Medicine recommended observational studies comparing adverse health outcomes of fully vaccinated children to children under-vaccinated due to parental choice. Misclassification of vaccination status could bias such studies. OBJECTIVE: To assess risk of misclassification of vaccination status within the Vaccine Safety Datalink (VSD). DESIGN/ METHODS: A retrospective cohort study was conducted in three phases. In phase 1, electronic health record (EHR) data were used to identify patterns of under-vaccination during the first 24months of life potentially due to parental choice. In phase 2, a random sample of records of under-vaccinated children was manually reviewed. In phase 3, a separate sample of parents were surveyed to assess whether EHR data accurately reflected their child's vaccination status. Phases 1 and 2 were conducted at 6 VSD sites, phase 3 at 1 site. RESULTS: The study cohort included 361,901 children born 2004 through 2012. By 24months of age, 198,249 (54.8%) were fully vaccinated with no delays, 84,698 (23.4%) experienced delays but were fully vaccinated by 24months of age, 4865 (1.3%) received no vaccines, 3789 (1.0%) delayed starting vaccination until ≥4months of age, 4781 (1.3%) had consistent vaccine-limiting (≤2 vaccines per visit), and the remaining 65,519 (18.1%) were missing vaccine series or doses. When a diagnosis code for vaccine refusal was present in EHR data, encounter notes confirmed vaccine refusal as the reason for under-vaccination for nearly 100% of sampled records. Parent surveys confirmed these findings. Parents of under-vaccinated children were more likely to report visiting an alternative medical provider than parents of fully vaccinated children. CONCLUSIONS: Specific groups of children, under-vaccinated due to parental choice, can be identified with relatively low likelihood of misclassification of vaccination status using EHR-based vaccine data and diagnosis codes.
BACKGROUND: To address public concern about the safety of the childhood immunization schedule, the Institute of Medicine recommended observational studies comparing adverse health outcomes of fully vaccinated children to children under-vaccinated due to parental choice. Misclassification of vaccination status could bias such studies. OBJECTIVE: To assess risk of misclassification of vaccination status within the Vaccine Safety Datalink (VSD). DESIGN/ METHODS: A retrospective cohort study was conducted in three phases. In phase 1, electronic health record (EHR) data were used to identify patterns of under-vaccination during the first 24months of life potentially due to parental choice. In phase 2, a random sample of records of under-vaccinated children was manually reviewed. In phase 3, a separate sample of parents were surveyed to assess whether EHR data accurately reflected their child's vaccination status. Phases 1 and 2 were conducted at 6 VSD sites, phase 3 at 1 site. RESULTS: The study cohort included 361,901 children born 2004 through 2012. By 24months of age, 198,249 (54.8%) were fully vaccinated with no delays, 84,698 (23.4%) experienced delays but were fully vaccinated by 24months of age, 4865 (1.3%) received no vaccines, 3789 (1.0%) delayed starting vaccination until ≥4months of age, 4781 (1.3%) had consistent vaccine-limiting (≤2 vaccines per visit), and the remaining 65,519 (18.1%) were missing vaccine series or doses. When a diagnosis code for vaccine refusal was present in EHR data, encounter notes confirmed vaccine refusal as the reason for under-vaccination for nearly 100% of sampled records. Parent surveys confirmed these findings. Parents of under-vaccinated children were more likely to report visiting an alternative medical provider than parents of fully vaccinated children. CONCLUSIONS: Specific groups of children, under-vaccinated due to parental choice, can be identified with relatively low likelihood of misclassification of vaccination status using EHR-based vaccine data and diagnosis codes.
Authors: James Baggs; Julianne Gee; Edwin Lewis; Gabrielle Fowler; Patti Benson; Tracy Lieu; Allison Naleway; Nicola P Klein; Roger Baxter; Edward Belongia; Jason Glanz; Simon J Hambidge; Steven J Jacobsen; Lisa Jackson; Jim Nordin; Eric Weintraub Journal: Pediatrics Date: 2011-04-18 Impact factor: 7.124
Authors: Elizabeth T Luman; Lawrence E Barker; Kate M Shaw; Mary Mason McCauley; James W Buehler; Larry K Pickering Journal: JAMA Date: 2005-03-09 Impact factor: 56.272
Authors: Sophia R Newcomer; Martin Kulldorff; Stan Xu; Matthew F Daley; Bruce Fireman; Edwin Lewis; Jason M Glanz Journal: Pharmacoepidemiol Drug Saf Date: 2018-01-02 Impact factor: 2.890
Authors: Jason M Glanz; Sophia R Newcomer; Matthew F Daley; Frank DeStefano; Holly C Groom; Michael L Jackson; Bruno J Lewin; Natalie L McCarthy; David L McClure; Komal J Narwaney; James D Nordin; Ousseny Zerbo Journal: JAMA Date: 2018-03-06 Impact factor: 56.272
Authors: Jason M Glanz; Nicole M Wagner; Komal J Narwaney; Jennifer Pyrzanowski; Bethany M Kwan; Carter Sevick; Kenneth Resnicow; Amanda F Dempsey Journal: Pediatrics Date: 2020-10-12 Impact factor: 7.124
Authors: Matthew F Daley; Jo Ann Shoup; Sophia R Newcomer; Michael L Jackson; Holly C Groom; Steven J Jacobsen; Huong Q McLean; Nicola P Klein; Eric S Weintraub; Michael M McNeil; Jason M Glanz Journal: Acad Pediatr Date: 2018-03-28 Impact factor: 3.107
Authors: Sophia R Newcomer; Rain E Freeman; Bekki K Wehner; Stacey L Anderson; Matthew F Daley Journal: Am J Prev Med Date: 2021-05-08 Impact factor: 6.604
Authors: Nicole M Wagner; Amanda F Dempsey; Komal J Narwaney; Kathy S Gleason; Courtney R Kraus; Jennifer Pyrzanowski; Jason M Glanz Journal: Vaccine Date: 2021-05-28 Impact factor: 4.169
Authors: Matthew F Daley; Liza M Reifler; Jo Ann Shoup; Komal J Narwaney; Elyse O Kharbanda; Holly C Groom; Michael L Jackson; Steven J Jacobsen; Huong Q McLean; Nicola P Klein; Joshua T B Williams; Eric S Weintraub; Michael M McNeil; Jason M Glanz Journal: Am J Prev Med Date: 2021-04-30 Impact factor: 5.043