Outgoing NHS boss Sir David Nicholson has said he "bitterly regretted" not speaking to patients and their families who were so badly treated during the Stafford Hospital scandal.

Sir David said not talking to campaigners and other patients was his "biggest mistake" during his 36 years of service in the NHS.

He avoided speaking to those affected because he did not want to be embroiled in a media circus.

NHS England's chief executive, who came under intense scrutiny for his role in the fiasco, spoke candidly and at length about his role in the scandal at a health care conference in Manchester.

With just 27 days left in the hot seat, Sir David spoke about a visit to the troubled hospital after a damning report into Stafford Hospital was published in 2009.

He told delegates at the Health and Care Innovation Expo in Manchester: "The biggest and most obvious mistake that I made was when it became clear when the Health Care Commission reported on Mid Staffordshire and I went to the hospital and I didn't seek out the patients representatives and the people who were in Cure The NHS, and I didn't do it because I made the wrong call.

"At the time Andy Burnham had been out and it had been turned into a media circus and I judged I didn't want to be involved in a media circus and I was wrong, I was absolutely wrong.

"Because one of the things I leaned, and I have determinedly done it since then, is that there is not shortcut to understanding and talking to patients and relatives and people, there is no shortcut to it.

"I didn't do it and then I got myself into a tangle of talking to people through the media, and that continues to be a very bad thing.

"That was a mistake that I made that I bitterly, bitterly regret."

In the past Sir David said that part of his decision to stand down was driven by "becoming the story" in the wake of the scandal.

Campaigners called for him to be sacked after the publication of the public inquiry report into Mid Staffordshire NHS Foundation Trust.

He was in charge of the regional health authority responsible for the trust for a short period while patients were being mistreated.

Speaking about his short tenure in the Midlands, Sir David said: "This is a hard conversation to have because whatever you say you sound defensive.

"I was the chief executive of the Birmingham and Black Country Strategic Health Authority, a pretty successful strategic health authority in lots of ways, and I was asked to take on the responsibilities for Shropshire and Staffordshire Strategic Health Authority and West Midlands South, as well as my job. I did each of them on one day a week.

"It was just closing them down because there had already been the decision made to reorganise them.

"Clearly I should have done more and I don't deny any of that at all.

"I worked in Birmingham and Black Country for thee years and about eight months in the rest of the West Midlands.

"With hindsight now, we should have taken more action quicker."

Mid Staffordshire was the focus of one of the biggest scandals in the history of the NHS.

Inquiries into the scandal revealed that hundreds more people died at the trust than would have been expected.

Some patients were left lying in urine and excrement for days, forced to drink water out of vases or given the wrong medication.

The 2009 investigation by the Healthcare Commission found that between 400 and 1,200 more people died at the trust than would have been expected.

And Robert Francis QC, chair of the public inquiry, highlighted the "appalling and unnecessary suffering" of hundreds of patients.

The trust was recently dissolved and key services will move to neighbouring hospitals.

Julie Bailey, who set up the campaign group Cure the NHS after her mother Bella died at the hospital, said that Sir David had "ample opportunity" to speak to the campaign group but never chose to do so.

"It is very easy to say when he is leaving and looking for a consultancy role," she said. "He had ample opportunity to come and meet us.

"Andy Burnham did not come to meet us and it was not a media circus."