The four-hour A&E waiting time target is a pledge set out in the NHS Mandate. The operational standard is that at least 95% of patients attending A&E should be admitted, transferred or discharged within four hours.
The Government's mandate to NHS England for 2018-19 put the four-hour waiting time target on hold. It stated that the NHS must "deliver aggregate A&E performance in England above 90% in September 2018, with the majority of trusts meeting 95% in March 2019, and aggregate performance in England at 95% within the course of 2019".
This indicator explores breaches of the four-hour A&E target since 2008. For in-depth analysis of what's causing increasing A&E waits, see our report Focus on: A&E attendances.
See also our Combined Performance Summaries, which present up-to-date information on some 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 & 3, such as single specialty departments or minor injury units) nearly always treat people in less than four hours, but major (type 1) A&Es deal with a higher number of attendees and more serious cases, meaning they find it harder to achieve the four-hour target.
The percentage of patients attending A&E that were admitted, transferred or discharged within four hours rose dramatically with the introduction of the 98% target in January 2004, and this target was met in Q2 2005/06. Over the next five years, performance varied between 96% and 98% and while there were large increases in the number of people using minor A&Es, increases in major A&E attendances were modest.
The relaxation of the target to 95% in 2010 was associated with an increase in patients waiting more than four hours in major A&Es, but performance initially remained close to or above the new target. By Q4 2017/18, performance had fallen dramatically to 76.8%, the worst level since the introduction of the four-hour target. In Q1 2018/19, performance recovered slightly to 84.4% but was still significantly below the target. Meanwhile, the total number of A&E attendances has been increasing over time, reaching over 6.2 million attendances in Q1 2018/19.
The impact of "winter pressures" on A&E performance against the four-hour target is apparent. There is a general trend for performance to be higher in the summer, despite the fact that A&E sees the highest numbers of attendees at this time. This is explained by changes in the case-mix of people attending. In summer A&E sees 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 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. 2017/18 followed a similar trajectory to 2016/17 until December 2017 when performance worsened. Unlike 2016/17, there was no recovery in February or March, and performance against the four-hour target continued to decrease before reaching an all time low of 76.4% in March 2018. By June 2018, performance had recovered slightly to 85.6%, but subsequently dropped to 83.5% in July.
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 by all patients. Overall, the median waiting time remained at around 130 minutes until the second half of 2014 when it began to increase. Since 2016 the median wait for all patients has fluctuated at around 150 minutes, peaking in March 2018 at 160 minutes.
In June 2018, admitted patients spent on average 229 minutes waiting in A&E. This was over one and a half times as long as the median waiting time for non-admitted patients, which reached 130 minutes in the same month.
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 has changed little since 2011 and ranges from a low of 46 minutes in January 2015 to a high of 69 minutes in March 2016.
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 223 minutes in March 2016. Since then, the 95th percentile value has fluctuated at a higher level of about 210 minutes. A peak of 237 minutes was reached in March 2018. It's worth noting that this measure can be sensitive to data quality issues.
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 line on this chart shows that the percentage of admitted patients waiting over four hours between the decision to admit and admission is highest in winter months and has increased substantially since 2010. In July 2018, 7.8% of patients breached the four-hour target. 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 2018 at 1,054. Whilst this is very small in comparison to the total number of people attending A&E departments, it is clear that a growing number of patients are waiting an extremely long time to be admitted onto a ward.
About this data
The NHS Improvement Chief Executive wrote to trusts in October 2017, which resulted in some trusts altering reporting in two ways:
a) Including non-co-located Type 3 attendances in their own returns
b) Including "new pathways of care" in their returns
The UK Statistics Authority subsequently raised concerns. An assessment exercise has now raised questions over the inclusion of up to 26,000 pathways of care per month in October, November and December 2017. It is estimated that national A&E performance in previous months could have been affected by between 0.11 to 0.18 percentage points. NHS trusts have confirmed that none of this "new activity" was included in performance reporting for January and February.
For more information, please see the Urgent & Emergency Care Attendances January 2018 Commentary.