Download
1 / 9
90 likes | 93 Views
What does the evidence actually tell us?. Evaluating Headlines. Hang-gliding or horse-riding?. The data: In 1985, 15 people died in horse-riding accidents, compared to one death from hang-gliding. Is the headline reasonable? What else might you need to know to make a judgement?.
E N D
What does the evidence actually tell us? Evaluating Headlines
Hang-gliding or horse-riding? The data: In 1985, 15 people died in horse-riding accidents, compared to one death from hang-gliding. • Is the headline reasonable? • What else might you need to know to make a judgement? “Hang-gliding is safer than horse-riding … to judge by a new survey of sports deaths.” The Times, 12 March 1987
Horse-riding or motor-cycling? The data: In 2007, it was reported that you could expect a serious motorbike accident every 7000 hours, compared to a serious riding accident every 350 hours. • Is the headline reasonable? • What else might you need to know to make a judgement? “… riding has now overtaken motorcycling as the biggest cause of rural casualties” The BBC 23 March 2007
Comparing risks • 1 micromort is defined as a 1 in a million chance of dying • 1 million micromorts is a mort, and means certain death. In order to compare risks of different activities, we need a common ‘currency’ or unit or risk.
Comparing risks 1 micromort is equivalent to: • 230 miles in a car • 6000 miles in a train • 3 flights 1 micromort is a 1 in a million chance of dying
Comparing risks • A general anaesthetic in a UK hospital carries a risk of 5 micromorts, on average, equivalent to: • riding a motorcycle 30 miles • riding in a car 1000 miles • going on one scuba-dive • living 4 hours as a heroin user • or serving 4 hours in the UK army in Afghanistan 1 micromort is defined as a 1 in a million chance of dying 1 million micromorts is a mort, and means certain death.
Comparing risks • UK service personnel are exposed to an average of 33 micromorts per day • equivalent to riding a motorcycle from London to Manchester • of course, front-line troops are exposed to considerably greater risks, as this is an average figure. 1 micromort is defined as a 1 in a million chance of dying 1 million micromorts is a mort, and means certain death.
Comparing risks • 1 hang-gliding flight is equivalent to 8 micromorts. • 1 ride on a horse is equivalent to half a micromort. • 6 miles on a motorcycle is equivalent to 1 micromort. 1 micromort is a 1 in a million chance of dying What do you think? Which is most dangerous?
