Background
In July 2017, NHS England announced a new set of performance targets for the ambulance service. The new standards are set out in the addendum to the Handbook to the NHS Constitution. The redesigned system is a triage system which focuses on a patient's clinical needs and aims to ensure that the highest quality and most appropriate response is provided for each patient first time. Since early 2021, however, ambulance response time targets have consistently been missed.
Ambulance services are measured by the time it takes from receiving a 999 call to a vehicle arriving at the patient's location. Under the system, all calls are triaged into four categories according to the patient's condition. Ambulances are now expected to reach people with life-threatening illnesses or injuries in an average time of 7 minutes. The 'clock' only stops when the most appropriate response arrives on scene, rather than the first.
NHS England published a plan for recovering urgent and emergency care services in January 2023, after witnessing a winter with some of the worst waiting times on record. A key area of focus was improving ambulance response times by increasing ambulance capacity. Although over 800 new ambulances were expected to be made available by 2023/24, only 300 new ambulances were reported to be operational by February 2024. Better forecasting of call demand and improved clinical assessment of calls was also part of the pipeline to ensure faster access to care. Operational planning guidance has been published for 2023/24, which includes an objective to improve Category 2 ambulance response timesto an average of 30 minutes, with further improvement to pre-pandemic levels in 2024/25. Here, we explore the performance of ambulance response times against targets for calls across all categories over time.
Ambulance response times to life-threatening situations
Category 1 ambulance calls are those that are classified as life-threatening and needing immediate intervention and/or resuscitation, e.g. cardiac or respiratory arrest. The national standard sets out that all ambulance trusts must respond to Category 1 calls in 7 minutes on average and respond to 90% of Category 1 calls in 15 minutes.
The average Category 1 response time improved from 7 minutes 44 seconds in May 2018 to 6 minutes 54 seconds in May 2019. Response times fluctuated for the following two years, with the 7-minute target last being met in April 2021, with an average response time of exactly 7 minutes.
Since then, Category 1 response times have deteriorated. An average response time of over 9 minutes was first recorded in September 2021. Since then, most months have seen average response times of over 9 minutes. In December 2022, the response time crossed 10 minutes, the worst performance on record. A palpable improvement has been observed since then. In May 2024, the average response time was 8 minutes 16 seconds, and the 90th centile target was met.
In May 2024, around 13% of incidents fell under Category 1, which covers a wider range of conditions than the former Red 1 category (which only included cardiac arrest patients who were not breathing and did not have a pulse, and other severe conditions). Performance against the previous target, that 75% of Category A (immediately life-threatening) calls should receive a response within 8 minutes, had been declining and was last met in January 2014.
Ambulance response times to emergency situations
Category 2 ambulance calls are those that are classed as an emergency or a potentially serious condition that may require rapid assessment, urgent on-scene intervention and/or urgent transport. For example, a person may have had a heart attack or stroke or be suffering from sepsis or major burns. All ambulance trusts should respond to Category 2 calls in 18 minutes on average and respond to 90% of Category 2 calls in 40 minutes. In January 2023, an additional objective was added to respond to Category 2 calls in 30 minutes on average for 2023/24. This national target also features in the 2024/25 NHS objectives.
The intent for Categories 2, 3 and 4 is to ensure that patients in these categories who require transportation receive a conveying resource in a timeframe that is appropriate to their clinical needs. Therefore, if a patient requires transportation in an emergency, the clock will only stop when the conveying resource arrives.
From the introduction of the Category 2 targets in April 2018, both the average and 90th centile response time targets were not met until April and May 2020. This came alongside a fall in the number of Category 2 incidents following the onset of the Covid-19 pandemic, to a low of 323,047 incidents in May 2020 – 16% lower than in May 2019.
Since then, Category 2 response times worsened considerably up until December 2022, which saw an average response time of 1 hour 33 minutes. The 90th centile response time was also the poorest on record during that month, at 3 hours 42 minutes. After December 2022, improvement occurred just as dramatically as the deterioration preceding it, but performance began worsening again towards the end of 2023. In December 2023, average response times had been brought up to 45 minutes 57 seconds. The response times for Category 2 calls has slightly decreased since, reaching 30 minutes 22 seconds in April 2024. In May 2024, it crept up to 32 minutes and 44 seconds, and 90% of people were responded to within 1 hour 8 minutes. During the 2023/24 period (April 2023 to March 2024), the average response time for Category 2 calls was 36 minutes 15 seconds, above the new objective of 30 minutes.
Ambulance response times to urgent situations
Category 3 ambulance calls are those that are classified as urgent. They are problems (not immediately life-threatening) that need treatment to relieve suffering (e.g. pain control) and transport or clinical assessment and management at the scene. The national standard states that all ambulance trusts must respond to 90% of Category 3 calls in 120 minutes. There is no target for the average response time.
Following the onset of the Covid-19 pandemic, response times fluctuated considerably. Between April and July 2020, Category 3 response times initially improved, with a fastest mean response time of 29 minutes in May 2020. This may be due to ambulance trusts bringing in additional staff from other services, or reduced traffic during the national lockdown.
Since then, response times for Category 3 calls have deteriorated. In December 2022, the mean response time was 4 hours 19 minutes and one in ten urgent cases waited over 11 hours for an ambulance. Since the following month, response times improved considerably, but the last few months of 2023 saw an increase in response times, although not as high as was seen in 2022. By May 2024, 90% of urgent cases waited for up to 4 hours 45 minutes (or 2 hours on average) until they were responded to. While this is an improvement compared with the end of 2023, it is still about 2 hours 45 minutes longer than the target.
Ambulance response times to less urgent situations
Category 4 ambulance calls are for incidents that are not urgent but need assessment (face-to-face or telephone), and possibly transport, within a clinically appropriate timeframe. According to the national standard, 90% of Category 4 calls should be responded to within 180 minutes.
Response times for Category 4 calls fluctuated between May 2018 and March 2021, when the 90th centile target was last met, with 90% of calls responded to within 2 hours 55 minutes. Following this, performance worsened rapidly; four months later the 90th centile response time exceeded 8 hours. Most months since June 2021 have seen average response times of over 3 hours and the poorest 90th centile and average response times were seen in December 2022. Overall improvement in ambulance responses has since occurred, and in May 2024, the 90th centile response time was 5 hours 29 minutes (still above the national standard by about 150 minutes) and the mean response was 2 hours 21 minutes – a slight setback from April 2024.
About this data
On 13 July 2017, the Secretary of State for Health accepted NHS England's recommendation to implement new ambulance performance standards. The new standards had already been piloted in three areas of England and clinical experts agreed that they would improve patient outcomes. They were progressively rolled out across the rest of England and, since April 2018, all 11 ambulance services have provided data on the new systems indicators.
Ambulance trusts use one of the approved triage tools to allocate incidents to one of the new response categories as quickly and accurately as possible. The response categories are as follows:
Category 1: Life-threatening
Time critical life-threatening event needing immediate intervention and/or resuscitation, e.g. cardiac or respiratory arrest; airway obstruction; ineffective breathing; unconscious with abnormal or noisy breathing; hanging.
Category 2: Emergency
Potentially serious conditions (ABCD problem) that may require rapid assessment, urgent on-scene intervention and/or urgent transport.
Category 3: Urgent
Urgent problem (not immediately life-threatening) that needs treatment to relieve suffering (e.g. pain control) and transport or assessment and management at the scene with referral where needed within a clinically appropriate timeframe.
Category 4: Non-urgent
Problems that are not urgent but need assessment (face-to-face or telephone) and possibly transport within a clinically appropriate timeframe.
The Addendum to the NHS Constitution requires all ambulance trusts to:
- Respond to Category 1 calls in 7 minutes on average and respond to 90% of Category 1 calls in 15 minutes.
- Respond to Category 2 calls in 18 minutes on average (amended to 30 minutes for 2023/24 and 2024/25) and respond to 90% of Category 2 calls in 40 minutes.
- Respond to 90% of Category 3 calls in 120 minutes.
- Respond to 90% of Category 4 calls in 180 minutes.
The previous response time commitments were set out in the NHS 2010/11 Operating Framework. They stated that:
- 75% of Category A (immediately life-threatening) calls should receive a response within 8 minutes.
- If a Category A patient requires transport, this should arrive within 19 minutes of the request for transport being made, 95% of the time.
From June 2013, the former Category A call category was further separated into Red 1 and Red 2 calls:
- Red 1 calls were the most time critical, covering cardiac arrest patients who were not breathing and did not have a pulse, and other severe conditions.
- Red 2 calls were serious but less immediately time critical, covering conditions such as stroke and fits.
For more information please see NHS England's Ambulance Quality Indicators.