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OS data helps keep hospital open in Somerset

Ordnance Survey data provided critical evidence leading to Somerset Clinical Commissioning Group keeping stroke services at two hospitals.


OS data provided critical evidence to keep stroke services at two hospitals.

In 2014, Somerset Clinical Commissioning Group (CCG) looked into how a proposed centralised stroke service, based at Taunton Hospital, would affect the population of Somerset as a whole.

Public Sector Mapping Agreement (PSMA) data from Ordnance Survey provided critical evidence leading to Somerset CCG keeping stroke services at both Yeovil and Taunton hospitals.

The operational challenge

A major service review recommended that closing the stroke services at Yeovil Hospital would benefit patients clinically.

However, the review posed the following challenges:

  • Research into how the proposed changes would impact such a large county, measuring 1,330 square miles and 70 miles across, was critical before any decision was implemented.
  • A sophisticated analytical tool was needed to confirm the review's findings.


The solution

The South West Commissioning Support (SWCS) Unit’s Geographical Information System (GIS) team used innovative analytical techniques with MapInfo Professional, RouteFinder and Basemap’s TRACC system – designed to quickly and accurately calculate various travel times.

Maps and reports were produced showing travel access times to the two current hospital sites at Taunton and Yeovil. These included blue light emergency transport times, private and public transport options, population numbers within travel times, and locations of stroke cases.

"This is the biggest project we have been involved with in the last few years, in terms of impact and influence GIS has had on NHS decision making."
Trevor Foster, SWCS GIS Manager.

The data driven benefits

  • Complex information on travel times and the potential implications on patients was presented in an easy to understand way. This evidence-based information resulted in accurate decision making.
  • The GIS study confirmed that the clinical benefits of closing Yeovil Hospital would be less than anticipated. In fact, the increased travel times would have a critical impact on the speed of treatment for many stroke patients.
  • The critical evidence informed the planning process and led to Somerset CCG deciding to retain both stroke services, substantially altering the direction of the review.
  • The methodology and techniques used are easily replicable for other geographical areas.

From 1 April 2020, the Public Sector Mapping Agreement (PSMA), was superseded by the Public Sector Geospatial Agreement (PSGA).

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