A theory-driven approach to understanding the effect of ethnic density on mental ill-health in England

This thesis examines the pathways behind the so-called ‘ethnic density effect’, whereby individuals from minority ethnic backgrounds have better health when they live in areas where they are more numerous. Despite a long-standing interest in the effect, little progress has been made in elucidating the pathways by which it operates. This thesis sought to address this gap using a theory-driven approach, in which existing knowledge was used to guide the research and analysis decisions made. Firstly, a systematic review was conducted to collate and evaluate UK-based evidence on the ‘ethnic density effect’ on mental health and on the pathways which have been proposed. From the results, a conceptual framework showing these proposed pathways was created. Guided by this framework, analyses of a sample of minority ethnic respondents from Wave 3 (2011-2013) of the survey Understanding Society, linked to area level census data, were conducted. A novel application of Structural Equation Modelling (SEM) was employed which allowed specification of both multilevel and multigroup components. The primary pathways identified by the systematic review were: racism, social support, social cohesion and social stress. Evidence for the ‘ethnic density effect’ and its pathways varied across ethnic groups. Through performing a Multi-Group Multilevel SEM, it was possible to test two paths: social cohesion and racism. Factor analysis was applied to the measurement of social cohesion, revealing a two-factor structure (social capital and belonging) which were invariant at the metric level across ethnic groups. In the final model no paths to or from social cohesion were statistically significant. However, a negative association between ethnic density and racism was found in three ethnic groups and a full indirect path for one ethnic group. The findings of this thesis are relevant to local governments in understanding the health implications of the geographical distribution of minority ethnic groups.