State-generated vaccine recall letter for Medicaid-enrolled children aged 19–23 months — Montana, 2011 Randall J. Nett, MD, MPH CDR, United States Public Health Service Career Epidemiology Field Officer — assigned to Montana 2012 Annual CSTE Conference June 5, 2012 Office of the Director Career Epidemiology Field Officer Program

Background  Advisory Committee on Immunization Practices (ACIP)  Recommends children aged 0–18 months receive routine vaccinations for protection against 14 vaccine-preventable diseases  National Immunization Survey (NIS) — 2009  Estimated coverage for recommended modified series (Hib excluded) for children aged 19–35 months Nationally = ~70% Montana = 61.7% (lowest quintile among states)

Vaccine Reminder/Recall Systems  Reminder/recall systems alert the parents of children due (reminder) or overdue (recall) for vaccinations  Task Force on Community Preventive Services recommends use of reminder/recall systems  Effective at increasing child/adult vaccination coverage  Healthcare provider  Academic center  Health department Jacobson VJ, Szilagyi P. Patient reminder and patient recall systems to improve immunization rates. Cochrane Database Syst Rev. 2005(3):CD

Vaccine Reminder/Recall System Variables  Method (telephone, letter, postcard, chart, etc.)  Population (adult, pediatric, privately insured, Medicaid, rural, urban, etc.)  Vaccine (series, influenza, single vaccine, etc.)  Schedule (one-time vs. multiple)  Intensity (one attempt vs. repeat attempts until contact)

Vaccine Reminder/Recall Systems  Irregularly used by surveyed U.S. physicians  28% of pediatricians  19% of Family Medicine physicians  Only 21% of surveyed Montana physicians caring for adolescents reported using reminder/recall systems  Not previously used by Montana Department of Public Health and Human Services (DPHHS) 1. Oster NV, McPhillips-Tangum CA, Averhoff F,,Howell K. Barriers to adolescent immunization: a survey of family physicians and pediatricians. J Am Board Fam Pract 2005; 18:

Methods  Identified children enrolled in Montana Medicaid with birthdates December 2, 2008–May 1, 2009  Data as of December 28, 2010 entered into Comprehensive Clinic Assessment Software Application  Medicaid billing data through December 1, 2010  Montana’s Web-based ImmuniZation Registry Database (WIZRD)  Medicaid Billing Data  Claims submitted to DPHHS following completion of services  Average 4-week delay from service to submission of billing claim  Prior to this study, billing data not used for public health purposes

Methods  Children enrolled in study if not known to have received each vaccine in study vaccination series

Study Vaccination Series  ≥4 doses of diphtheria, tetanus toxoid, and acellular pertussis vaccine (DTaP)  ≥3 doses of inactivated poliovirus vaccine (IPV)  ≥1 dose of measles, mumps, and rubella vaccine (MMR)  ≥4 doses of Haemophilus influenzae type b conjugate vaccine (Hib)  ≥3 doses of hepatitis B vaccine (HepB)  ≥1 dose of varicella vaccine (VAR)  ≥4 doses of pneumococcal vaccine (PCV)

Study Vaccination Series

Methods  Children randomly selected to intervention or control cohorts  Intervention cohort = parents sent recall letter on January 21, 2011  Control cohort = no recall letter sent  Used addresses listed in Montana Medicaid  If letter returned, re-sent using address listed in WIZRD, if different  Vaccination coverage assessed at baseline and in June 2011 for vaccines received through April 30, 2011  SAS® Enterprise Guide

Recall Letter  Generalized letter  No mention of specific vaccines  Urged parents to visit their healthcare provider to be brought up-to-date  Sent one-time

Results 1865 Medicaid enrolled children aged 19–23 months

Results 1865 Medicaid enrolled children aged 19–23 months 987 children excluded

Results 1865 Medicaid enrolled children aged 19–23 months 878 children eligible to participate 987 children excluded

Results 1865 Medicaid enrolled children aged 19–23 months 878 children eligible to participate 987 children excluded 440 (50%) children not sent letter

Results 1865 Medicaid enrolled children aged 19–23 months 878 children eligible to participate 987 children excluded 438 (50%) children sent recall letter 440 (50%) children not sent letter

Results 438 children sent recall letter

Results 438 children sent recall letter 355 (80%) letters not returned

Results 438 children sent recall letter 355 (80%) letters not returned83 (20%) letters returned undeliverable

Results 438 children sent recall letter 355 (80%) letters not returned83 (20%) letters returned undeliverable 45 letters re-sent

Results 438 children sent recall letter 355 (80%) letters not returned83 (20%) letters returned undeliverable 45 letters re-sent 38 letters not resent

Study Participants (n = 878)  Male = 464 (53%)  Median age = 21 months  American Indian/Alaskan Native (AI/AN) = 184 (21%)  Rural or frontier county = 768 (87%)  Number of missing vaccines  1–2 = 357 (41%)  3–5 = 204 (23%)  6–10 = 121 (14%)  11–20 = 196 (22%)  No significant difference in above characteristics between intervention and control cohorts (p>0.05)

Coverage for Selected Vaccines at Baseline *P-value >0.05 for each vaccine

Coverage for Study Vaccination Series at 3 Months *P-value >0.05 for each characteristic

DTaP — % Increase in Coverage from Baseline *P-value >0.05 for each dose

HepB — % Increase in Coverage from Baseline *P-value >0.05 for each dose

Hib — % Increase in Coverage from Baseline *P-value >0.05 for each dose

IPV — % Increase in Coverage from Baseline *P-value >0.05 for each dose

MMR — % Increase in Coverage from Baseline *P-value >0.05 for 1 st dose

PCV — % Increase in Coverage from Baseline *P-value >0.05 for each dose **P-value <0.05 for each dose

VAR — % Increase in Coverage from Baseline *P-value >0.05 for 1 st dose

Discussion  Single, state-generated recall letter resulted in limited increase in vaccination coverage among predominantly rural Medicaid-enrolled children aged 19–23 months  No statistically significant increase in coverage for study vaccination series  Significant increase in third and fourth dose of PCV  Non-statistically significant increase in coverage for some antigens  Study demonstrated specific reminder/recall systems not effective in every setting  Study described potential use for Medicaid billing data

Why Less Successful than Other Studies?  Letter was sent one-time only  Letter was generalized and not more specific  Letter originated from DPHHS and not individual healthcare provider  Letter might not be preferred delivery method for younger parents  Rural population  Other confounders

Influences on Vaccination Coverage  Parental beliefs and attitudes  Perceived low-risk from vaccine preventable diseases  School entry, childcare entry, and work entry requirements  Access to healthcare  Cost of vaccines  Healthcare provider practices

Influences on Vaccination Coverage  Parental beliefs and attitudes  Perceived low-risk from vaccine preventable diseases  School entry, childcare entry, and work entry requirements  Access to healthcare  Cost of vaccines  Healthcare provider practices  Healthcare provider beliefs and attitudes  Office practices  Personal emphasis placed on immunizations  Use of reminder/recall systems

Influences on Vaccination Coverage  Parental beliefs and attitudes  Perceived low-risk from vaccine preventable diseases  School entry, childcare entry, and work entry requirements  Access to healthcare  Cost of vaccines  Healthcare provider practices  Healthcare provider beliefs and attitudes  Office practices  Personal emphasis placed on immunizations  Use of reminder/recall systems

Limitations  Letters not sent by certified mail  Potential delay in healthcare provider billing  Only 93% of public healthcare providers and 74% of private healthcare providers known WIZRD users  Medical records of study participants not reviewed

Conclusions  Vaccine reminder/recall systems effective at increasing vaccination coverage  Single state-generated recall letter sent to parents of Montana Medicaid-enrolled children aged 19–23 months had limited effectiveness  Medicaid billing data are important source of public health data

Recommendations  Clinicians should use reminder/recall systems to improve vaccination coverage among their patients  State and local health departments should use reminder/recall system(s) most likely to improve vaccination coverage in their population  Users of reminder/recall systems should evaluate system to determine effectiveness and adjust strategy  Public health authorities should conduct further research to identify effective reminder/recall systems

Next Steps  imMTrax  Montana’s new IIS  Higher functionality  Advocating for vaccination providers to use reminder/recall systems  Alternative reminder/recall methods  Continued use of Medicaid billing data for public health purposes

For more information please contact Centers for Disease Control and Prevention 1600 Clifton Road NE, Atlanta, GA Telephone: CDC-INFO ( )/TTY: Web: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. Office of the Director Career Epidemiology Field Officer Program Carolyn A. Parry Steven D. Helgerson Cody L. Custis James S. Murphy Carol Ballew Eric Higginbotham Acknowledgments Bekki Wehner Kathleen Grady Vicci Stroop Heather Zimmerman

Patient Preferences for Reminder/Recall Systems Clark SJ, Butchart A, Kennedy A, Dombkowski KJ. Parents’ experiences with and preferences for immunization reminder/recall technologies. Pediatrics 2011;128:e1100–5.