198458 A neighborhood and spatial measure of racial isolation applied to birthweight

Monday, November 9, 2009: 1:05 PM

Rebecca Anthopolos, MA , Children's Environmental Health Initiative, Duke University, Durham, NC
Sherman A. James, PhD , Public Policy Studies, Duke University, Durham, NC
Alan Gelfand, PhD , Institute of Statistics and Decision Sciences, Duke University, Durham, NC
Marie Lynn Miranda, PhD , Children's Environmental Health Initiative, Duke University, Durham, NC
Research has shown that racial residential segregation is associated with poor birth outcomes among blacks in the United States. As the most conceptually sound dimension of segregation to capture where and under what conditions mothers live, racial isolation has been widely applied in these studies. Traditional measures of racial isolation aggregate population counts at the neighborhood level over a large geographical area without accounting for population composition in adjacent neighborhoods. This approach, however, is limiting because it precludes studying the effects of racial isolation within a given region, assumes mothers within a region face the same risk, and over- or underestimates racial isolation by ignoring spatial relationships among neighborhoods. To better characterize racial isolation within the framework of modeling birthweight, we developed a measure that allows within-region variation, reduces dependence on neighborhood boundaries, and is applicable at refined geographical scales. Using the North Carolina Detailed Birth Record (1999-2001), we use multiple linear regression to model the effect of racial isolation on birthweight, adjusting for maternal age, education, and parity. To explore whether birthweight is spatially patterned, we employ a Conditional Autoregressive (CAR) model to adjust for residual spatial autocorrelation. We show that racial isolation at the neighborhood level is associated with a decrease in birthweight of similar magnitude as the presence of maternal risk factors, including whether a mother has completed high school or is over 40 years of age. There is evidence that birthweight is a spatial process, which suggests the importance of accounting for spatial dependence in estimation.

Learning Objectives:
1. Formulate a new measure of racial isolation that is applicable at a neighborhood level and accounts for spatial relationships among neighborhoods. 2. Show that racial isolation at a neighborhood level is associated with decreased birthweight, adjusting for maternal characteristics. 3. Evaluate the pros and cons of the corresponding birthweight model with spatial random effects.

Keywords: Birth Outcomes, Epidemiology

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am the primary statistician for the analysis described in this abstract. I have an M.A. in Economics from Duke University and am currently an Associate in Research at the Children's Environmental Health Initiative at Duke University.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

See more of: Social Epidemiology
See more of: Epidemiology