The most senior doctor in the NHS today warned against acceptance of unsafe and poor-quality care as he addressed the country’s biggest patient safety conference.

Professor Sir Bruce Keogh told the Patient Safety Congress at Birmingham’s ICC that investigations into the Bristol Royal Infirmary and into Mid Staffordshire Hospitals had shown that good, caring people found themselves accepting increased risk to patients despite recognising that something was wrong in their care and treatment.

The medical director of NHS England said this came from a range of factors, including the belief that “things happen” and there is nothing individuals can do to stop them, as well as staff feeling unable to challenge established practices and more senior colleagues.

Sir Bruce told the conference: “Acceptance is different from complacency, and can be insidious and dangerous.

“When you know something is not quite right and feel a little uncomfortable and you tell yourself that maybe it’s not so bad after all, you are accepting poor practice. The reasons for this can be a mixture of emotion, embarrassment, fear of upsetting professional colleagues, and sometimes just a general sense of convenience.

“When that happens, you lose your professional and personal compass, and that’s the danger.

“What’s galling is that you get good, caring people who do nothing, because they have fallen prey to acceptance.”

He called on the NHS to embrace precautionary principles and ensure investigation wherever there was a suspicion of harm being caused, saying: “At both the Bristol Royal Infirmary and Mid-Staffordshire Hospitals, arguments about statistics and data continued while more and more patients were being harmed.

“If Marks and Spencer spot a salmonella risk in their chicken sandwiches, they recall them straight away – they don’t wait for someone to become ill. Acceptance of that precautionary principle in the NHS could be our greatest friend, could help negate the need for delayed inquiries into known failings, and could be truly transformational.”

Sir Bruce referenced key points in his own career, including the lead-up to the publication of cardiac surgeons’ success rates, and more recent work with the Royal College of Surgeons to reduce incidence of deep-vein thrombosis, and called on the health sector to monitor and understand their own performance.

He said: “People who are providing clinical services should be able to describe what they do and define how well they do it. We can’t accept people continuing to so operations without knowing what their results are.

“Patient safety, in my view, is all about the culture. Leaders of organisations in our NHS system need to provide freedom for people to speak, freedom for people to lead, and freedom for people to follow. Importantly, they need to give time for the changes to happen.”