The number of patients waiting more than four hours for treatment in accident and emergency departments has increased by 63% since the health secretary, Andrew Lansley, scrapped the waiting time target imposed by the previous government.

An extra 73,000 patients were left to wait for over four hours in the last three months of 2010 compared with the previous year, according to data obtained by BBC Newsnight.

Mid Staffordshire NHS Trust had the most patients facing long waits, at 10% of the total and more than three times the number a year before. At Barnsley Hospital NHS Foundation Trust, the number of patients waiting over four hours increased sixfold in a year, to just over 5%.

The shadow health secretary, John Healey, condemned the increases. "This sudden jump in lengthy waits at A&E will raise further concerns about the government's handling of the NHS," he said.

In total, 184,000 patients waited more than four hours in A&E departments between September and December 2010. If the increased numbers remained the same over a full year, it would mean an extra 300,000 patients facing long waits compared with a year before.

The number of patients waiting over four hours increased in 129 of the 149 trusts where data was available.

A spokesperson for the Department of Health said: "It is completely misleading to look at A&E waiting times without taking into consideration the overall increase in A&E attendances. The reality is that last year around 2.2% of people waited in A&E for over four hours; now it is only 3.5%.

"Doctors and nurses told us that the four-hour standard was not always clinically effective as it focused on time alone. That is why this month we have introduced a new set of clinical quality indicators to provide a more balanced and comprehensive view of the quality of care.

"These indicators include clinical effectiveness, safety and service experience as well as timeliness and will allow the NHS to focus on measuring its performance on what matters most – patient outcomes."

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