Karen Wooten, MA Elizabeth Luman, MS Lawrence Barker, PhD Assessing Childhood Vaccination Coverage in The U.S. by Socioeconomic Status, 1999-2002: Does Income Affect Outcome? Karen Wooten, MA Elizabeth Luman, MS Lawrence Barker, PhD

Background Childhood vaccination coverage is at an all-time high Socioeconomic Status (SES)– one of the most powerful predictors of Health For Good Health, studies report it helps to be Rich Persistent Low vaccination coverage among children are associated with living in poverty defined households (Klevens, M; Luman, E)

Research Questions What effect does Socioeconomic status have on childhood vaccination coverage rates? Which is a better predictor of Vaccination Coverage in Children: Mother’s Education or Socioeconomic Status? When socioeconomic status and mother’s education factors are accounted for, do racial disparities in vaccination coverage persist?

Methods: Data Used National Immunization Survey (NIS), 1999-2002 Children between 19 and 35 months of age Random Digit Dialed (RDD) Telephone Survey Parents reported vaccination history via telephone Providers reported vaccination history via Mail Weighted for national representation of children 19-35 months of age

Methods: Outcome Measure Vaccination Coverage is based on up-to-date status of the 4:3:1:3 Series: 4+ doses of Diphtheria and Tetanus toxoids and pertussis vaccine 3+ doses of any poliovirus vaccine 1+ doses of measles-containing vaccine 3+ doses of Haemophilus Influenzae type B vaccine Only children with provider-reported vaccination histories were included in the analysis

Methods: SES Measures Mother’s Education: H.S. or lower vs. > H.S. Socioeconomic Status (SES)- 6 levels: Severe poverty (ratio < 50%) Intermediate poverty (ratio 50 to < 100%) Near poverty (ratio 100 to <125%) Low middle SES (ratio > 125-300%) Middle SES (ratio >300-600%) Upper SES (> 600%) above poverty

Methods: Other Explanatory Measures Geographic: Region (Northeast, Midwest, South, West) Population Density (Urban, Suburban, Rural) Demographic: Race/Ethnicity (Non-Hispanic White, Non-Hispanic Black, Hispanics, Other) Marital Status (currently married vs. not married) .

Methods: Analysis Strategy Analysis conducted using SUDAAN Software Package Survey analysis tool for complex sample survey data Chi Square Test for Trends Bivariate and Multivariate Logistic Regression: Wald Chi Square Tests of Significance Odds Ratios (Crude and Adjusted)

Results

Vaccination Coverage (4:3:1:3 Series) by Socioeconomic Status

Childhood Vaccination, 1999-2002: Up to date for 4:3:1:3 Series by Mother’s Education

Likelihood of Vaccination (Adjusted Odds Ratios) by Socioeconomic Status and Mother’s Education Status Levels: 1999 2000 2001 2002 Severe (<50% poverty) .71* .82 .86 .91 Below (50-100%) .81* .97 .94 1.01 At (100%-125%) .81 1.13 .88 Low (125%-300%) Reference Middle (300%-600%) 1.15 1.37* 1.38* 1.43* Upper (>600%) 1.24 1.86* 1.83* Education: < H.S. > H.S. 1.30* 1.26* 1.29*

Influence of Socioeconomic Status and Mothers’ Education on Race/Ethnicity Household SES 1999 2000 2001 2002 White, Non-Hispanic √ Black, Non-Hispanic Hispanic Mother’s Education Adjusted by Demographic and Geographic Factors

Influence of Socioeconomic Status and Mother’s Education on Influence of Socioeconomic Status and Mother’s Education on *Race/Ethnicity Base Model 1999 2000 2001 2002 Whites 1.24 1.33 1.51 Hispanics 1.03 1.34 1.27 Other 1.07 1.05 1.28 1.42 *Black children represent the reference group

Influence of Socioeconomic Status and Mothers’ Education on Influence of Socioeconomic Status and Mothers’ Education on *Race/Ethnicity Base Model 1999 2000 2001 2002 Whites 1.24 1.33 1.51 Hispanics 1.03 1.34 1.27 Other 1.07 1.05 1.28 1.42 Base Plus Socioeconomic Status Model: 1.09 1.19 1.40 1.11 1.30 1.43 0.94 1.20 1.38 *Black children represent the reference group

Influence of Socioeconomic Status and Mothers’ Education on Influence of Socioeconomic Status and Mothers’ Education on *Race/Ethnicity Base Model 1999 2000 2001 2002 Whites 1.24 1.33 1.51 Hispanics 1.03 1.34 1.27 Other 1.07 1.05 1.28 1.42 1999 2000 2001 2002 Base Model: Plus Mother’s Education Whites 1.24 1.30 1.29 1.47 Hispanics 1.12 1.11 1.44 1.37 Other 1.03 1.05 1.26 1.39 *Black children represent the reference group

Influence of Socioeconomic Status and Mothers’ Education on Influence of Socioeconomic Status and Mothers’ Education on *Race/Ethnicity Base Model 1999 2000 2001 2002 Whites 1.24 1.33 1.51 Hispanics 1.03 1.34 1.27 Other 1.07 1.05 1.28 1.42 Base Model: Plus SES and Education 1999 2000 2001 2002 Whites 1.09 1.21 1.19 1.42 Hispanics 1.16 1.07 1.33 1.48 Other 0.93 1.05 1.20 1.38 *Black children represent the reference group

Influence of Socioeconomic Status and Mothers’ Education on Influence of Socioeconomic Status and Mothers’ Education on *Race/Ethnicity Base Model 1999 2000 2001 2002 Whites 1.24 1.33 1.51 Hispanics 1.03 1.34 1.27 Other 1.07 1.05 1.28 1.42 Base Model: Plus Socioeconomic Status 1.09 1.19 1.40 1.11 1.30 1.43 0.94 1.20 1.38 1999 2000 2001 2002 Base Model: Plus Socioeconomic Status and Mother’s Education Whites 1.09 1.21 1.19 1.42 Hispanics 1.16 1.07 1.33 1.48 Other 0.93 1.05 1.20 1.38 *Black children represent the reference group

Summary of Findings Children living in upper SES households are vaccinated more often than children living in lower SES households Of the two factors -Socioeconomic Status (SES) and Mother’s Education, SES is the strongest independent predictor of vaccination coverage Mother’s education is a strong predictor of vaccination coverage Is not a significant factor in reducing racial disparities

Limitations Some vaccination providers were not identified, did not respond to the NIS, or did not complete Incomplete medical records may result in underreporting of up-to-date vaccination status Age and interval appropriateness of vaccinations were not taken into account

Conclusions Racial differences in vaccination coverage may be due to differences in socioeconomic status Differences between black, non-Hispanic and White, Non-Hispanic may be due to an additive or multiplicative effect of socioeconomic status and mother’s education Persistent disparities in coverage between Hispanic children and Non-Hispanic Black children may be due to the types of interventions that target the Hispanic population.