The four-hour A&E waiting time target is a pledge set out in the Handbook to the NHS Constitution. The operational standard is that at least 95% of patients attending A&E should be admitted, transferred or discharged within four hours.
In March 2019, the Review of NHS Access Standards was published, which proposed that the current four-hour A&E target should be replaced by a set of access standards, including the average waiting time in A&E, time to initial clinical assessment, and time to emergency treatment for critically ill and injured patients. NHS England selected 14 hospital trusts to field test the new standards, and an interim report was published in October 2019. NHS England has consulted on the proposed new standards, and the response to the consultation states that the new standards will be rolled out. The existing four-hour target remains in force until any new standards are announced. Read the latest Nuffield Trust blog for more information about the proposed A&E targets.
This indicator explores breaches of the four-hour A&E target since 2010. For in-depth analysis of what's causing increasing A&E waits, see our report Focus on: A&E attendances. See also our NHS performance summaries, which present up-to-date information on key NHS performance measures as data are released by NHS England.
The length of time patients spend in A&E depends on the type of A&E unit they visit. Minor A&Es (types 2 and 3, such as single specialty departments or minor injury units) nearly always treat people in less than four hours, but major A&Es (type 1) deal with a higher number of attendees and more serious cases, meaning they find it harder to achieve the four-hour target.
The target for the percentage of patients attending A&E that are admitted, transferred or discharged within four hours was relaxed from 98% to 95% in 2010. Performance initially remained close to or above the new target. By Q3 2019/20 (October to December 2019), performance had fallen dramatically to 72%, the worst level since the introduction of the four-hour target. The total number of A&E attendances had been increasing over time, reaching almost 6.5 million in Q3 2019/20.
In Q1 2020/21, the total number of A&E attendances fell dramatically to 3.6 million, following the outbreak of the coronavirus (Covid-19) pandemic, and waiting time performance improved sharply to 90%. This may reflect guidance to call NHS 111 with concerns about Covid-19 symptoms, as well as messaging encouraging people to stay at home during the national lockdown. A&E attendances increased to 5 million in Q2 2020/21 (July to September 2020), and performance worsened to 85%. By Q4 2020/21 (January to March 2021), the number of attendances had fallen to 4.3 million, but performance remained low with only 76% of patients spending less than four hours in A&E.
In summer 2020, pilots began for a ‘call first’ model of urgent care, where patients with an urgent medical need were asked to call NHS 111, and those recommended to attend A&E were given a booked time slot to attend. Between Q2 2020/21 and Q4 2020/21, the total number of booked attendances at A&E increased from 43,980 to 164,195 (data not shown). In Q4 2020/21, this represented only 3.8% of total A&E attendances.
The impact of winter pressures on performance against the four-hour A&E target is apparent. There is a general trend for performance to be higher in the summer, despite the fact that A&Es see the highest numbers of attendees at this time. This is explained by changes in the case-mix of people attending. In summer, A&Es see a higher proportion of cuts and sprains, most of which can be treated relatively quickly. In winter, there is a larger proportion of older people attending and a greater number of people requiring emergency admission to hospital.
Drops in performance are normally observed from November in any given financial year. Performance generally recovers at least partially by April the following year.
On the whole, there has been a year-on-year decrease in the proportion of patients attending major A&E departments that are admitted, transferred or discharged within four hours. In 2019/20, there was a substantial drop in performance, falling to an all-time low of 69% in December 2019.
In May 2020, after the outbreak of Covid-19, performance increased to 91%, however this came alongside a substantial fall in A&E attendances, with 33% fewer type 1 A&E attendances in May 2020 than in May 2019. As A&E attendances increased, performance worsened and in May 2021, only 76% of patients were admitted, transferred or discharged within four hours – the worst performance for any May since records began.
As well as looking at the proportion of patients attending A&E who are admitted, transferred or discharged within four hours, we can also study the median number of minutes spent in A&E. The median waiting time for all patients increased from 129 minutes in May 2011 to 174 minutes in December 2019, before falling to 135 minutes in May 2020 during the Covid-19 outbreak. Since then, the median waiting time has increased to 165 minutes in April 2021.
For patients who required admission to hospital, the median A&E waiting time remained below four hours until September 2019. Note that the four-hour A&E target is for 95% of patients to be seen in four hours, while the median represents 50% of patients. In December 2019, the median wait increased dramatically to 321 minutes. This may reflect the increase in trolley waits (the time patients wait from when a decision is made to admit and them being admitted, see below) in the winter of 2019. In June 2020, the median waiting time for admitted patients fell to 210 minutes, before increasing to 234 minutes in April 2021.
The median waiting time for non-admitted patients was 86 minutes lower in April 2021, at 148 minutes.
Median waits are routinely published by NHS Digital each month, but the new A&E standards will measure the mean time in A&E for admitted and non-admitted patients (not currently published). It is worth noting that these data are provisional and sensitive to poor data quality (see ‘About this data’ for more information).
While adherence to the four-hour target is the iconic measure of A&E performance, the length of time between patients arriving in A&E and their treatment beginning is another important indicator. This chart shows that the median treatment waiting time changed little between May 2011 and February 2020, ranging from a low of 46 minutes in January 2015 to a high of 70 minutes in November 2019. In April 2020, the median treatment waiting time fell to 24 minutes, following the decrease in A&E attendances during the Covid-19 outbreak. The median treatment waiting time increased to 57 minutes in April 2021.
Interestingly, the 95th percentile value – that is, waiting times for some of the patients that wait the longest – fluctuated at around 185 minutes until August 2015, before increasing to a high of 277 minutes in December 2019. In April 2020, the 95th percentile value fell dramatically to 121 minutes, before increasing to 230 minutes in May 2021. It’s worth noting that this measure can be sensitive to data quality issues.
The Review of NHS Access Standards intends to measure the time to emergency treatment for critically ill and injured patients. It proposes introducing a package of treatment to be completed in the first hour after arrival for life-threatening conditions such as stroke, heart attack, major trauma, asthma and acute physiological deterioration (including sepsis).
For patients that require admission to a hospital ward, the time they wait between the A&E unit deciding that they should be admitted and the patient actually arriving on the ward is very important. The number of patients waiting over four hours and over 12 hours between the decision to admit and admission is highest in the winter months and has increased over time. In January 2021, 95,695 admitted patients waited over four hours. The peak in January 2021 (21% of admitted patients waiting over four hours) was higher than in January 2020 (18%) and January 2019 (15%).
During the Covid-19 pandemic, the number of admitted patients waiting over four hours between the decision to admit and admission fell to a low of 13,457 in May 2020 (3.4% of emergency admissions), 78% lower than in May 2019. This corresponds to a considerable fall in A&E attendances and emergency admissions.
The bars on the chart show the number of people waiting over 12 hours to arrive on a ward. The number of extreme waits peaked in January 2021 at 3,825. While this is only 0.9% of total emergency admissions in January 2021, the number of patients waiting an extremely long time to be admitted onto a ward has grown substantially since 2010.
About this data
NHS England data
In March 2019, the Clinically-Led Review of NHS Access Standards Interim Report was released, proposing some significant changes to A&E waiting time targets. A six-month Progress Report from the NHS Medical Director was also published in October 2019.
Field testing of the proposed new standards began in 14 hospital trusts on 22 May 2019. The first stage of testing focused on measuring the “mean time in A&E”, when compared to the existing four-hour target. The field test sites have not been submitting four-hour performance data since May 2019, so an adjusted national time series was published to omit these sites’ A&E performance going back to Q1 2011/12. The time series data presented here for performance against the four-hour target excludes the field testing sites and so is comparable across months and years. Data on A&E attendances is for all trusts, including the field testing sites.
In January 2018, the NHS Improvement chief executive Ian Dalton wrote to trusts to announce a formal review of the reporting of A&E performance data. The letter refers to issues in two main areas: the reporting of urgent care (type 3) activity, and the reporting of activity from newer clinical pathways, such as ambulatory care services.
It followed the UK Statistics Authority writing to NHS England to formally raise concerns about the impact of changes to recording practice and the interpretation that should be applied. This prompted questions of whether the data was reliably measuring pressure and performance over winter.
In November 2018, the UK Statistics Authority stated that its concerns had been addressed, however, some concerns still remain about the quality of performance data. For more information, see the most recent HSJ article.
NHS Digital data
Median waiting time in A&E and time to treatment have been calculated using provisional Emergency Care Data Set (ECDS) data since June 2020. Prior to then, they were calculated using provisional A&E Hospital Episode Statistics (HES) data. The measures used have not changed, although data quality measures are still to be developed. Provisional HES and ECDS data may be revised throughout the year. As these indicators are published on a monthly basis rather than in a time series, indicator data published for earlier months have not been revised using updated HES or ECDS data extracted in subsequent months.
NHS Digital notes that several organisations report data that does not meet the data quality checks required by A&E indicators, which contributes to why unusually high values may be observed for some measures.