Bridging the Gap: A Quantitative Analysis of Black and White Infant Mortality Disparities in the United States

BACKGROUND:   In most counties in the US, Black infant mortality is twice as high as White infant mortality. Though overall infant mortality has been declining for some time now, the disparity persists. These inequalities should be investigated in order to implement appropriate interventions and close the gap between Whites and minorities in the US. This study serves to assess the strength of association between Black infant mortality rates and White infant mortality rates with respective poverty rates and percentage of residents living in urban areas as well as percentage Black or White living in that county.

METHODS:   A cross-sectional data analysis was conducted using data from the CDC mortality database (2008-2010) and the American Community Survey (2008-2010), both cross-sectional surveys, was conducted. Robust regression was used to identify outlier counties and multiple regression was used to assess the evidence of association separately for Black and White infant mortality and the Black:White infant mortality rate ratio and a selection of independent variables. The independent variables were Black Poverty or White Poverty, percent of the Black or White population living in an urban setting and the  percent of the population that is Black or percent of the population that is White. Further analysis was performed to account for clustering within states.

RESULTS:   The interpretation of results did not differ between regression strategies. Percent of the Black population living in poverty was found to be statistically significant in association with Black infant mortality. This association was stronger for White poverty and White infant. The poverty ratio and the ethnic ratio were not found to be associated with the Black:White infant mortality rate ratio. Counties identified as outliers in terms of infant mortality rates, poverty, ethnic composition, rate ratios or a combination of those factors did not exhibit consistent  patterns in their characteristics. The counties that had infant mortality rates in significant excess of the mean had average poverty rates.

CONCLUSIONS: Disparities in infant mortality were not explained by the OLS or robust regression models in this study even after clustering within states was accounted for.  No significant associations were found in the models for the Black:White infant mortality rate ratios. The reduction and elimination of ethnic disparities in US infant mortality will require interventions that specifically target structuralized racism and other factors that contribute to poor health outcomes