It's a failing of the entire medical system that is putting the lives of patients at risk, say researchers from the Stanford School of Medicine.

Doctors who are exhausted or suffering from burnout are twice as likely to make a mistake that could endanger the life of the patient. In a survey of 6,695 doctors, 55 per cent said they had recently suffered symptoms of exhaustion and burnout, and 10 per cent admitted they had made at least one major medical error in the previous three months.