Social Factors and Infant Mortality: Identifying High-Risk Groups and Proximate Causes

This paper examines relationships among six social factors and infant mortality in California in 1978 and seeks to explain social differentials in terms of two intervening variables. Linked birth and infant death records are analyzed to test for interactions among the social factors and mortality and for causal linkages involving the intervening variables. Social factors are related to the risk of infant mortality in a conditional manner; significant interactions involve maternal age and both birth order and marital status, and race/ethnicity and both education and marital status. Birth weight and prenatal care are important intervening variables but do not fully explain the social differentials.