1. Zhen Zhao, PhD and Holly A. Hill, MD, PhD
Trends in hepatitis B birth dose vaccination coverage disparities by birth year cohort for children in the United States, 2005–2014
Zhen Zhao, PhD and Holly A. Hill, MD, PhD
2018 Joint Statistical Meetings, Vancouver, Canada
Date: July 28 – August 2, 2018

2. 1. Introduction
In 1991, the United States adopted a strategy for universal hepatitis B vaccination of infants [1].
Universal HepB birth dose vaccination coverage, defined as 1 dose of vaccine administered by 3 days of life, increased from 50.1% in 2003–2005 to 71.1% in 2016 [2],
Coverage is still below the Healthy People 2020 target of 85% [3].
Disparities in HepB birth dose vaccination coverage for sociodemographic factors by birth year cohort have not been investigated.

3. 2. Objectives
Evaluate the disparities in hepatitis B (HepB) birth dose vaccination coverage by selected sociodemographic factors, by birth year cohorts from 2005 to 2014 among young children in US.
Estimate changes in disparities in HepB birth dose vaccination coverage by birth year cohort across 2005–2014.
Describe the trends in disparities as narrowed/widened, across birth year cohorts.

4. 3. Methods
National Immunization Survey-Child (NIS-Child) data were used to generate birth year cohorts for the year
Disparities in HepB birth dose vaccination coverage by selected sociodemographic subgroups were independently evaluated.
Slopes from weighted linear regression of HepB birth dose coverage disparities across the birth cohorts were used to estimate the average change in disparities per birth year, and to determine whether disparities narrowed/widened over time.

5. 4. Results

6. Table 1.1 Significant disparities in HepB birth dose vaccination coverage by selected sociodemographic factors for birth year cohorts , United States
Socio-demographic categories compared
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
Children health insurance insured vs uninsured
13.5
( 5.9,21.2)
9.1
( 1.2,17.0)
14.8
( 6.4,23.2)
Child first born yes vs no
Non-Hispanic black vs Non-Hispanic white
4.6
( 0.6, 8.6)
7.3
( 3.6,11.0)
6.2
( 2.2,10.2)
4.9
( 0.4, 9.4)
7.6
( 2.7,12.4)
Hispanic vs Non-Hispanic white
3.9
( 0.3, 7.4)
( 0.5, 7.3)
4.0
( 0.5, 7.5)
6.3
( 2.7,10.0)
4.5
( 0.5, 8.5)
6.1
( 2.2,10.0)
8.4
( 4.5,12.3)
Children with >= 2 vs 1 provider
10.0
( 7.0,12.9)
9.6
( 6.7,12.4)
8.1
( 5.3,10.9)
( 1.3, 6.8)
4.4
( 1.6, 7.2)
All public vs all private providers
( 2.0,10.6)
5.8
( 0.6,11.1)

7. Table 1.2 Significant disparities in HepB birth dose vaccination coverage by selected sociodemographic factors for birth year cohorts , United States
Socio-demographic categories compared
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
Mother education ≤12 vs ≥13 years
5.3
( 2.6, 8.0)
4.3
( 1.6, 6.9)
4.0
( 1.3, 6.7)
6.1
( 3.5, 8.7)
6.9
( 4.2, 9.5)
4.5
( 1.7, 7.3)
3.9
( 0.8, 7.0)
( 1.3, 7.3)
( 1.4, 7.6)
Mother not married vs married
3.1
( 0.0, 6.2)
5.6
( 2.6, 8.6)
5.0
( 2.1, 8.0)
8.0
( 5.3,10.8)
8.4
( 5.7,11.0)
6.5
( 3.6, 9.4)
( 3.8,10.0)
6.6
( 3.5, 9.8)
3.8
( 0.1, 7.5)
9.5
( 5.4,13.6)
Mother’s age <=29 vs >=30
6.3
( 3.5, 9.2)
5.7
( 2.9, 8.4)
( 3.3, 8.8)
6.0
( 3.3, 8.6)
4.8
( 2.1, 7.5)
3.6
( 0.8, 6.4)
( 2.0, 8.0)
4.1
( 1.1, 7.0)
( 0.9, 7.1)
Family with >=2 children vs 1 child
5.2
( 0.7, 9.6)
Family did not move vs moved
8.3
( 3.2,13.3)
( 4.4,14.5)
8.7
( 3.9,13.5)
12.5
( 7.5,17.5)
13.0
( 7.2,18.9)
9.6
( 4.9,14.3)
14.4
( 8.1,20.7)
Below vs at/above poverty
( 1.1, 8.0)
( 1.1, 7.5)
4.7
( 1.7, 7.6)
9.4
( 6.7,12.1)
( 3.9, 9.9)
( 2.8, 9.5)
( 2.0,10.6)

8. Average change in disparity %
Table 2. Average change in disparity per birth year across 2005–2014 in HepB birth dose vaccination coverage by sociodemographic factors among young children in the United States.
Socio-demographic
categories compared
Average change in disparity %
(95%CI) per year
Significance status
Disparities narrowed
(-) or widened (+)
Health insurance insured vs uninsured
0.63 (-1.9, 3.2) No
Widened
Mother education ≤12 vs ≥13 years
-0.15 (-0.44, 0.15)
Narrowed
Family with >=2 children vs 1 child
0.28 (-0.17, 0.74)
Mother not married vs married
0.29 (-0.21, 0.78)
Mother age <=29 vs >=30
-0.34 (-0.49, -0.19)
Yes
All public vs all private providers
-0.64 (-1.33, 0.04)
Family did not move vs moved
1.22 (0.75, 1.69)
Children with >= 2 vs 1 provider
-1.26 (-1.69, -0.83)
Child first born yes vs no
-0.31 (-0.63, 0.004)
Non-Hispanic black vs Non-Hispanic white
0.23 (-0.26, 0.72)
Hispanic vs Non-Hispanic white
0.73 (0.28, 1.17)
Below vs at/above poverty
0.13 (-0.47, 0.72)

9. Table 2 indicated:
The disparities for mother’s age ≥30 vs. ≤29 years, and for children with 1 vs. ≥2 providers narrowed significantly over time, with an average change of -0.34% and -1.26% per year respectively (P-value <0.05). (Figure 1).
The disparities for families that did not move vs. moved, and for Hispanic vs. Non-Hispanic white children significantly widened over time; the corresponding average changes in disparities were 1.22% and 0.73% per year (P-value < 0.05). (Figure 2).

14. Figure 3 shown that the trend of disparities for mother education ≤12 vs ≥13 years, all public vs all private providers, and child first born yes vs no narrowed but not significant during the birth year cohort period of
The trend of disparities for Health insurance insured vs uninsured, family with >=2 children vs 1 child, mother not married vs married, Non-Hispanic black vs Non-Hispanic white, and below vs at/above poverty widened but not significant during the same birth year cohorts period as presented in Figure 4.

15. 5. Limitation
NIS uses a list-assisted random-digit-dialing (RDD) design in household survey which could result in bias in evaluation of HepB birth dose vaccination coverage due to non-response and exclusion of households without telephone service. However, recent publications have shown that the total survey errors with NIS are very small.
Linear trend lines were fıtted to visually clarify whether disparities were tending to narrow or widen over time. The actual relationship between disparities and time could be nonlinear. However, linear regression usually captures the major variation of the practical trend line, and has been used widely in medical publications. Actually, in this study the R-Squares of the linear regressions are 0.8, i.e. the linear trend explains most of the variability of practical trends.

16. 6. Conclusions
Disparities in coverage with the HepB birth dose by socio-demographic factors are common among U.S. children born in years
The disparities for mother’s age ≥30 vs. ≤29 years, children with 1 vs. ≥2 providers, families that did not move vs. moved, and Hispanic vs. Non-Hispanic white changed significantly across birth year cohorts
Overall vaccination coverage with the HepB birth dose has increased over time, but disparities in coverage remain. Administration of this vaccine should be made a routine part of neonatal care for all babies born in the United States.

17. 6. References
[1]. CDC. Hepatitis B virus: a comprehensive strategy for eliminating transmission in the United States through universal childhood vaccination. Recommendations of the Immunization Practices Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 1991;40(No. RR-13):1–25.
[2]. Hill HA, Elam-Evans LD, Yankey D, Singleton JA, Kang Y. Vaccination coverage among children aged 19–35 months—United States, MMWR Morb Mortal Wkly Rep 2017;66:1171–7.
[3]. US Department of Health and Human Services, Office of Disease Prevention and Health Promotion. Healthy people Washington, DC: US Department of Health and Human Services;

18. For more information please contact: Zhen Zhao, PhD
Centers for Disease Control and Prevention,
1600 Clifton Road NE, Atlanta, GA
Disclaimer:
The findings and conclusions in this presentation are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention.

19. Thank you!