Staff at a Nottingham hospital "bent rules" on recording patient waiting times due to "enormous pressure" to hit targets, a review has found.
Independent auditors were brought in to the Queen's Medical Centre after inaccurate reporting of waiting times over the past four years was uncovered.
The hospital has to treat 98% of patients within four hours to meet government targets.
Auditors said patients were not put at risk.
The report states: "Some staff described the enormous pressures they felt under to achieve the four-hour A&E target and deliver patient care at the same time."
This was a failure of our systems
The review of the department, which is one of the busiest in England, was sparked after a member of the hospital's medical staff noticed by chance that a patient's time in A&E had been inaccurately reported.
The audit found 1,889 records had been wrongly recorded since April 2008.
It was concluded that most staff believed they were following the rules correctly, but when concerns were raised by a staff member in 2005 senior managers had not been informed.
The report found a lack of training, the absence of auditing of the recording system, "inadequate" systems in place for staff to raise concerns and a lack of management accountability contributed to the problem.
Peter Homa, chief executive of Nottingham University Hospitals NHS Trust, said lessons have been learned.
"The reports show that our internal processes and rules weren't as robust and clear as they should have been.
"This was a failure of our systems.
"We have already put in place new measures to improve, and to ensure that this issue cannot happen again."
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