Children’s heart surgery at Leeds General Infirmary was halted because of poor data showing unusually high death rates which were submitted by the hospital itself, the medical director of NHS England has said.

NHS England decided yesterday that operations could resume at the centre, 11 days after they were stopped amid fears that twice as many babies and children died at the unit compared with specialist facilities elsewhere in the country.

Sir Bruce Keogh said the initial decision to suspend children’s heart surgery in Leeds was necessary while NHS England investigated data which showed unusually high mortality rates at the unit.

He said that such drastic action was needed given the recent scandals at Stafford Hospital and in Bristol, which had occurred while doctors and managers “prevaricated” over what data meant.

Sir Bruce told the BBC Radio 4 Today programme: “The data had shown a higher mortality but that data was based on information submitted by the hospital itself.

“Leeds had not submitted good data to the National Audit which is used for monitoring the quality of children’s heart surgery.

“To give you an example, in order to take case mix into account so that we compare apples with apples and oranges with oranges, one of the simple things you need is… to know the weight of a baby.

“A 10-day-old baby weighs much more than a one-day-old baby but the weight was missing in 35 per cent of cases. But in all the other units of the country the amount of missing data in that area was 0 per cent to 1.4 per cent so that data was very poor quality.

“We have had two significant public inquiries - one into children’s heart surgery in Bristol and more recently into events at Mid Staffordshire, both of those costing over £10 million.”

The NHS had learned from those inquiries that in the past “people have argued and prevaricated over data to try and decide what it means, whether it is accurate, and whether people they should do anything, and they have hesitated over action,” he continued.

“So what I was putting to the trust was that, given the constellation of things were very serious, the most sensible thing to do in everybody’s interests, not only the babies and parents, was to halt the operations until we got to the bottom of it.”

The centre had been earmarked for permanent closure following a nationwide review of children’s cardiac services in England.

But campaigners successfully fought the ruling in the High Court only to see NHS England suspend surgery because of concerns about mortality rates at the centre, provoking anger and surprise among those who wanted to see the unit remain open.