In this week's BMJ, a group of senior doctors say they have no evidence that the four hour A&E target benefits clinical care. They also argue that it has encouraged target led rather than needs led care.
The UK four hour standard for processing patients attending emergency departments was introduced at 90% in 2004 and has sat at 98% since 2005, write Suzanne Mason and colleagues in a letter to the journal.
Last week, this target was relaxed to 95% by the new coalition government.
In 2005, the authors showed that patients admitted to hospital from the emergency department were affected most by a "spike" in activity during the last 20 minutes of the four hours, which affected 12.3% of admitted patients and 3.6% of discharged patients in 2004.
Now they set out to find out whether this spike was still occurring nationally.
They analysed 12.2 million new patient episodes at English emergency departments in 2008-2009. The data show that the spike is still present and larger than in 2004, affecting 30.7% of admitted patients and 10.5% of discharged patients.
"Although many in the specialty of emergency medicine support the benefits that the four hour target has brought, these results suggest that they are not being experienced by all patients, and that processes throughout the hospital and wider healthcare system may not have improved to accommodate it," they say.
"Good evidence based indicators of quality in emergency medicine need development," they add. "We have no evidence that the 98% four hour target benefits clinical care, and our findings suggest that it has encouraged target led rather than needs led care."
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