For harried doctors, there’s no more frustrating sight than an aggressive patient. When the NHS is under constant pressure, patients who appear to waste doctors’ time or behave rudely are easy targets for the contempt of the over-stretched staff.

This has important clinical impacts. Research published today in the British Medical Journal shows that aggressive or demanding patients are more likely to be misdiagnosed. This is because the effort of dealing with them distracts doctors from making sense of clinical information. In the study, doctors were 42 per cent more likely to misdiagnose a difficult patient who was displaying the symptoms of a complex condition.

This is no small problem, for the NHS is, according to recent reports, paying up to £4m a week in compensation to patients who are misdiagnosed and approximately 12,500 patients die every year because of medical blunders. A tenth of the money spent on compensation is paid out because doctors had missed the signs of cancer – a potentially fatal slip.