1. Using drivetime analysis to assess the availability of choice in maternity services Andrew Oliver, National Audit Office

2. Spatial analysis – maternity services drivetimes Calculated distance and time people had to travel to closest maternity service by type Darker the shading, further travel time to access choice Small geographic units - LSOA Uses publicly available data Required additional products to core GIS software Calculated distance from LSOA to maternity service to provide full data set for report

3. Calculating maternity services drivetimes – data sources Data sourced from the ONS website Downloaded files at LSOA level showing for both years Geography shapefiles Population by gender and age Data from the Department List of maternity service locations and service type as at 2007 and 2013 Combined files to show females aged 16-44 for each of approx. 32.5k areas Plotted LSOA population weighted centroids Plotted postcode locations using GIS

4. Mapping techniques Software requirements 1.Plotting points LSOA population weighted centroids (from) Location of maternity services (to) Standard GIS software 2.Processing Calculation of from-to time (and distance) between LSOA and nearest maternity service Drivetime add-in 3.Creating outputMapping the resultsStandard GIS software Calculating maternity services drivetimes – software Uses standard GIS software – MapInfo Professional Supplemented with drivetime add-in and road network

5. Calculating maternity services drivetimes – processing Drivetime software uses digital road network to plot route Nominal scale of 1:50,000 Route time and distance calculated using pre-defined fixed speeds Some adjustment for road type and conditions Sufficient precision for indicative analysis Load from and to sites Repeat to account for different maternity service types Repeat for both 2007 and 2013 To provide a full data set for report, calculated metrics from LSOA to maternity service rather than creating buffers from maternity service

6. Maternity services drivetime results Darker the shading, further travel time to access choice, in 2013: 79% of females aged 16-44 have both an obstetrics unit and a midwife led unit within a 30 minute drive 3% of females aged 16-44 have neither maternity service type within a 30 minute drive Access to choice has improved since 2007, with additional midwife led units opened 2007 2013