Pre-hospital emergency department data (PHED)

A project linking data across ambulance services and acute trusts in order to assess the potential for improving patient care.


Published: 30/08/2017

Project status: Completed

Ambulance services and emergency departments (EDs) collect data on patient care and store it electronically. However, in English ambulance services, there is no routine link made between the datasets. Each episode of emergency care for one patient will have two records, one held by the ambulance service, another by the ED. The physical handover of a patient and the continuity of clinical care from one organisation to the other is routine, but currently electronic data does not cohesively connect the patient journey.

Demand for ambulance services in England is rising at an average year-on-year increase of 5%. Meanwhile, services are under pressure to contain costs and improve quality. Data systems therefore have a part to play.

The Pre-Hospital Emergency Department Data Linkage project (PHED Data) was a two-year mixed methods research project funded by the Health Foundation as part of the 'Insight 2014' award funding stream. It aimed to assess the feasibility of and potential learning from retrospectively linking ambulance service data to ED data, using no patient-identifiable information, and creating a continuous electronic record of the patient journey from ambulance to ED.

PHED Data aimed to answer 3 questions:

1. What are the potential opportunities for and challenges to routinely linking data from the ambulance service to emergency departments?

2. What understanding can be gained from this linked data which could lead to the improvement of health care delivery within the ambulance service and across the wider health care economy?

3. What are the challenges to and opportunities for using these data to inform future commissioning of health care?

The project team was made up of our staff and researchers from Swansea University, the Nuffield Trust and Kingston University and St. George’s, The University of London.

The project ran for two years from May 2015. The team approached six more acute trusts across London and asked them for outcome data, which was linked to the existing records. They then analysed the resulting data set through a series of work packages looking at:

  • Response times
  • How other health care professionals use ambulance services
  • Patient groups that are acutely unwell in the ambulance
  • Patient groups that are not acutely unwell in the ambulance

We also conducted a series of focus groups and interviews with staff from across the NHS to help us interpret the findings. From this we produced a internal report and a series of recommendations. The findings were then submitted and subsequently published in journals and other publishing outlets. These outputs are listed below. 

Project outputs

Clark S, Halter J, Porter A, Smith HC, Brand M, Fothergill R, Lindridge J, McTigue M and Snooks H (2019) 'Using deterministic record linkage to link ambulance and emergency department data: is it possible without patient identifiers? A case study from the UK', International Journal of Population Data Science 4:1:20.

Clark S (2017) 'Five ways linking ambulance and A&E data could help to improve care'. Blog, The Health Foundation, 27 September.

Clark S, Porter A, Halter M, Damiani M, Dorning H, McTigue M (2017) 'Data linkage across ambulance services and acute trusts: assessing the potential for improving patient care'. Poster presentation, Emergency Medicine Journal 33(9): e12.

Clark S, Damiani M, Dorning H, Halter M and Porter A (2017) 'Patient-level data linkage across ambulance services and acute trusts: assessing the potential for improving patient care', International Journal of Population Data Science 1(1): 270, Proceedings of the IPDLN Conference.