Racial Residential Segregation and Birthweight: The Role of Specific Dimensions of Segregation

Janice F. Bell, University of Washington
Frederick J. Zimmerman, University of Washington
Gunnar R. Almgren, University of Washington
Jonathan D Mayer, University of Washington
Colleen E. Hueber, University of Washington

Five distinct dimensions of residential segregation have been identified empirically; however, there is little evidence to guide the measurement of segregation in studies of health. We developed a conceptual model and tested associations between segregation and birthweight in a sample of 494,248 singleton births to African-American or Black women living in 225 large U.S. Metropolitan Statistical Areas. In multilevel regression models of birthweight on the five segregation dimensions, isolation and clustering were significantly associated with birthweight in opposite directions. As hypothesized, higher isolation was associated with lower birthweight and higher clustering was associated with higher birthweight. While isolation appears to be deleterious to birthweight, aspects of racial contiguity appear to be mitigating, or indeed beneficial. These findings underscore the multidimensional aspects of segregation and the need for theoretically-driven measurement decisions that include the possibility of several segregation dimensions in a single analytic model.