Mapping

Mapping of ethnic densities was carried out to demonstrate their distribution in the geographical areas of investigation. To facilitate easier visualisation of this distribution, individuals were aggregated in the larger Middle Super Output Areas (an administrative area with an average population of 7787). The mapping was restricted to four ethnic groups: White, Bangladeshi, African and Caribbean, because of the low densities of the others [33]. Area-level ethnic density estimates were compiled from the current patient data, rather than relying on 2011 Census data, to ensure that they were up to date and as closely related as possible to the population under investigation [37].