How we remodelled ambulance services in England

England's National Ambulance Service provides care for millions of people every year. However, too often patients have been left waiting hours for care. But the University of Sheffield has helped to change all that, with a recent change being called the biggest overhaul for the service in 40 years.


Demand for the 999 ambulance service is much bigger than it used to be. In 1995 there were 3.5 million 999 calls a year to the UK’s emergency healthcare service number. Now there are 10 million. The demand for ambulance service care is at an unprecedented high, placing a huge strain on their staff and services.

It’s no secret that working for any emergency service can be gruelling at times and for the ambulance service it’s no different. 999 call handlers and paramedics alike work tirelessly to provide the best clinical care they can to patients in need. So how can outdated time-targets, and the allocation of limited and inadequate resources be revamped so staff can provide the best possible care?

There are 10 regional ambulance services in England dealing, on average, with between 1100 and 4500 emergencies a day. Faced with stretched resources and poor performance, in 2015 NHS England embarked on an ambitious programme of change to how 999 calls are triaged, categorised and responded to (the Ambulance Response Programme – ARP).

As part of this they approached Janette Turner, a Reader in Emergency and Urgent Care Research in the School of Health and Related Research at the University of Sheffield. Janette’s role was to provide academic input to the plans and carry out a comprehensive evaluation on the impact of the changes. This evaluation was crucial in ensuring that changes were evidence based and provided the information needed for NHS England and Ministers at the Department of Health to make decisions about national adoption of the changes.

Before the ARP changes, 50 per cent of all 999 calls had to be responded to within eight minutes. That’s eight minutes from the moment the call handler takes basic patient details  to the ambulance or paramedic arriving at the emergency. As soon as call handlers had an address they had to send someone if they were to stand a chance of getting there in 8 minutes. This didn’t leave enough time to determine the nature of the problem, or how urgent it was.

These unrealistic time targets also resulted in call handlers sending whatever resource was available. And often this wasn’t what was most appropriate for the patient. Consider somebody who’s had a stroke and calls 999. If all that’s available is a single paramedic in a fast response car then that’s what’s sent to the patient. However, what that patient really needs is to get to hospital as quickly as possible. This means another resource (a proper ambulance that can transport) will also have to be sent and this causes a delay. As a patient it’s much better to wait 20 minutes and get the right clinical care than have a paramedic arrive within 8 minutes only to have to wait another hour for an ambulance – all so the clock could be stopped.

It’s one thing to rush to an emergency without the right resources. But it’s another to also be somewhat in the dark about the severity of the situation itself. Unhelpful categorisation of emergencies has also played a role in increasing the strain on services. Originally, calls were categorised in one of three ways: 1) Red one, 2) Red two, 3) Green. Red one and two were the calls with an eight minute response time and comprised half of all calls coming through.

We know from previous work that half of people who call 999 don’t have a life threatening emergency, it’s more like 10 per cent of people. So they were trying to get to calls in eight minutes that just didn’t need such a rapid response. As a result those who did need it weren’t getting it because the services were spread too thin.

Janette Turner

Reader in Emergency and Urgent Care Research in the School of Health and Related Research, University of Sheffield

Ambulance Service graphic (2)

The approach to overhauling the Ambulance Service had three key aspects. The first was to give the call handlers in the control room more time before starting the clock. By spending more time on the call dispatchers can establish the problem and the level of urgency, giving a clearer picture of who’s most in need and what type of response is necessary. To support this some early questions were introduced so that time critical calls (such as cardiac arrest) would be identified early and sending help would not be delayed.This was tested in about half of the services in England.

Over the course of the testing period Janette looked at all kinds of measures; for example, how quickly they got to the problem and how appropriate the level of care was. As a result, there was a huge improvement in how efficiently resources were used because there were fewer instances of sending multiple resources to the same call. 

“We estimated this made more than 10,000 extra available resources each week across England. This also means a much higher number of patients were getting the right response first time. We also found that there was a 6.6% increase in the proportion of calls getting a response within 8 minutes. Importantly, when we asked ambulance service staff about this change they were overwhelmingly positive saying it helped them to better assess calls and manage the resources they had available,” says Janette.

Alongside this, the ARP completely revised the call categories and Janette played a key role in the process by using historical data to support the decisions made by clinical experts. It took three iterations but after a lot of testing the calls are now broken down into five categories rather than three. As Janette explains, “the biggest advantage of the new categories is that the highest category (category 1) is now about 10% of calls and captures the true life-threatening emergencies.

As a result these patients now get a much more consistent and rapid response than previously. In the 2.5 years since these changes were made, every ambulance service achieved and sometimes exceeded the response time standards for these calls even when demand is very high. A larger number of categories also allows much more discrimination that helps dispatchers decide on the right resource to send including specialist resources such as advanced and community-based paramedic services.”

New and improved call categories
  • Category one - These are the most urgent calls that need the fastest response, making up 10 per cent of all calls received. E.g. severe anaphylactic reaction, cardiac arrest, unconsciousness and breathing difficulties
  • Category two - Strokes, heart attacks,  road traffic accidents, serious injury, fits etc 
  • Category three and four - Here there’s no imminent danger. It tends to be incidents like a fall but where there’s no injury. Or people with quite vague symptoms eg. back pain or abdominal pain
  • Category five - For some calls an ambulance isn’t appropriate  and a patient may just need to talk to a clinician, particularly for symptoms that are not new or chronic illnesses for example.

The final change was to allocate each of the call categories their own response time standards. These are the most appropriate time for the category and level of urgency. For category one, the expectation is that they will get there within seven minutes on average. But for the lower priority categories there is a much longer response time. For example, for category three the response time is within two hours for 90 per cent of calls. 

Obviously people want the emergency services to come quickly but the reality is that you’re not going to come to any harm in those later categories and people were waiting that long anyway, it just wasn't being reported.

Janette Turner

Reader in Emergency and Urgent Care Research in the School of Health and Related Research, University of Sheffield

In July 2017, these new ambulance response standards were announced by NHS England after rigorous testing on ten million 999 calls. According to the Association of Ambulance Chief Executives Managing Director, Martin Flaherty OBE, “The introduction of the new ambulance response standards is positive for patients and ambulance services alike. Our control room staff and paramedics out on the road have welcomed the new system which has been developed with significant input from senior ambulance clinicians. We can also see clearly how the quality of care will improve for all patients because the new standards will mean greater availability of our limited resources, especially for those with life-threatening conditions who need us there fastest. It is a common-sense approach that is long overdue.”

The number of people calling 999 shows no sign of diminishing which will continue to create real challenges in a resource-limited service. But now, every time  an ambulance arrives at an emergency it’s much more likely to be the right resource in an appropriate time frame to provide the best clinical care to the patient at the other end. The changes that have been implemented were undoubtedly very significant in terms of how we respond to 999 calls. As Janette remarks, “there are far too many examples of change in the NHS that are not well thought through or evidence based. It was a privilege to work with NHS England and the Ambulance Response Programme as a valued partner throughout the entire process. Our work provided the robust information needed to support a critical policy change that is now firmly embedded as routine operational practice across England."

Written by Alicia Shephard, Research Marketing and Content Coordinator

Graphics by Ella Marke, Visual Designer

Further information

Janette Turner

Janette Turner, Twitter

Key research 

Outcomes for Patients Who Contact the Emergency Ambulance Service and Are Not Transported to the Emergency Department: A Data Linkage Study

Why do ambulance services have different non-transport rates? A national cross sectional study

Prioritizing novel and existing ambulance performance measures through expert and lay consensus: A three‐stage multimethod consensus study


New ambulance response standards introduced to improve patient care

For further information contact:

Amy Pullan
Media Relations Officer
University of Sheffield
+44 114 222 9859

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