Skip to main content

Table 1 Description of urban metrics quantifying patterns of population, road network, land cover and geographical characteristics

From: Associations between urban metrics and mortality rates in England

Theme Urban characteristic Urban metrics Data source Potential health related benefits Potential health related concerns
Population Population density Population density (pop/km2):
total city population over city area in square kilometres
ONS, Census 2001 High population density:
easy to walk/cycle
increase of physical activity [15]
High population density:
spread of infectious diseases
elevated air pollution levels
potential loss of green space
social stress
Road network Walkability of cities Minor road density (km/km2):
length in kilometres of minor roads and B roads over city area (km2)a
OS, Meridian 2 High minor road density:
easy to walk/cycle
increase of physical activity [15]
High minor road density:
elevated pollution levels
higher road traffic noise levels
Connectivity of road network Junction density (N/km2):
number of A roads, B roads and minor road junctions over city area (km2)a
OS, Meridian 2 High junction density:
easy to walk/cycle
increase of physical activity [15]
High junction density:
elevated air pollution levels
higher road traffic noise levels
increased number of road traffic accidents related to road junctions
Urban sprawl Population within 100 m of major roads (%):
proportion of postcode headcount population within 100 m of A roadsa
OS, Meridian 2; ONS, Census 2001   High population density close to major roads:
higher noise and air pollution exposure across city population
less likely to walk/cycle and reduction in physical activity [27]
increased number of road traffic accidents related to higher speed
Land cover Land cover mix Shannon’s diversity index (SDI) [31]:
H= i = 1 s p i ln p i
where p i is the proportion of land cover i relative to the total number of land cover classes
CEH, Land Cover Map 2000; EEA, CORINE Land Cover 1990 (vs 12/2000) High land cover mix:
easy to walk/cycle
increase of physical activity [15]
less car usage
lower air pollution levels
High land cover mix:
residential areas potentially close to polluted areas
Geographical characteristics Terrain Altitude range (m) OS, Land-Form PANORAMA Hilly terrain:
increase in physical exercise if walking or cycling
Hilly terrain:
Less likely to walk/cycle
  1. aRoad classification in the UK is classified by the Department of Transport (DfT) as follows: A roads connect areas of regional importance, B roads connect places of local significance and minor roads are roads without classification by the DfT, mostly local roads intended for local traffic [28]