Monday, 24 August 2015

Glasgow Health Inequalities

To further look at health inequalities and test the QGIS d3MapRenderer plugin further, the Scottish Index of Multiple Deprivation health domain was downloaded from the Scottish Government Website along with vector layers for Scottish Neighbourhood Statistics data zones, administrative and parliamentary boundaries from the UK Data Service Census Support Website.

The health domain rank is comprised of a number of indicators, namely: a standardised mortality ratio; hospital episodes related to alcohol use; hospital episodes related to drug use; comparative illness factor; emergency admissions to hospital; proportion of population being prescribed drugs for anxiety, depression or psychosis; and, proportion of live singleton births of low birth weight. The SIMD then weights each indicator to produce a combined rank for the health of the population at the level of Scottish Neighbourhood Statistics data zones. The SIMD health domain data was imported as a delimited text layer into QGIS, joined to the Scottish Neighbourhood Statistics data zones before being clipped to the boundary of Glasgow.

Building outlines for Glasgow were downloaded from the Ordnance Survey OS Open data VectorMap™ and were used to clip the data further so that only the built up areas of Glasgow are visible. Although the building outlines will include warehouses, offices and other large buildings, this is an easy way to overcome the problems of unstandardized choropleth maps relating to human geography where physically large but sparsely populated areas dominate the map. The SIMD health domain rank was then used to create a graduated colours map with ten categories and a quantile classification method, a method often used in epidemiology. This method allows comparisons to be made across the city rather than the health rank within the entire country.

The plugin can then be used to export the building outlines, with a legend and tooltip. No simplification is used during the export as this would introduce distortion of the buildings. A quick alteration of the tooltip html and the map is ready to upload onto a web server.

Deciles of health rank for Glasgow, with data from the Scottish Index of Multiple Deprivation, 2012. Contains Ordnance Survey data © Crown copyright and database right 2013. Pan and zoom around the map, click on a building to view the health domain data.