Scientific nonsense and relative risk

Assessing risk is something everyone must do every day.  Yet very few receive any formal training in the requisite mathematics and statistics, and, partly as a result, many poor decisions are being made, both by individuals and governmental bodies. Evolutionary biologist Richard Dawkins suggests that we may be neurologically ill-equipped to make the sort of decisions called for by modern society. Nobel prize-winning behavioural economist and psychologist Daniel Kahneman makes it clear in his book Thinking Fast and Slow that making careful (slow) judgements is a very complicated mental process.

For example, many have presumed that in the wake of the threat of terrorism, not to mention recent questions about safety of airliners, that air travel remains a rather dicey proposition. At least one dear colleague of ours refused to fly on an airplane out of fear of accidents. When one of us suggested that he simply buy some noise-canceling headphones, play some Bach and dream his way to his destination, he responded by saying headphones would impede his ability to hear malfunctions in the aircraft.

Yet little noticed by the public is an recent announcement that four full years have elapsed without a single airline fatality in the U.S., and 2012 was the safest year globally since 1945. The worldwide 2012 fatality figure (475 deaths) was less than half the figure in 2000, and most accidents occur in Africa where it is reasonable to expect significant improvement as economies grow.

With regards to fear of terrorist attacks, German psychologist Gerd Gigerenzer has estimated that in the first year after the September 11 terrorist attacks in 2001, 1500 Americans died in auto accidents because they elected to drive rather than fly (due to fear of dying in a sabotaged airplane). In other words, six times as many Americans needlessly died in autos in the year after September 11 than died in hijacked airplanes on September 11.

Similar nonsense can be seen in the fanatical and often counter-productive measures taken by parents to protect children. For example, in 1970, 67% of American children walked or biked to school, but today only 10% do, in part out of fear of abductions. Yet the number of cases of true child abduction by strangers (as opposed to, say, a divorced parent) has dwindled to only about 100 per year in the U.S. today. Even if one assumes that all of these children are harmed (which is not by any means true), this is still only about 1/20 the risk of drowning and 1/40 of the risk of a fatal car accident.

Such numerically absurd thinking can also be seen in the recent international hysteria over childhood vaccinations. This mania stemmed from a 1998 study in the British medical journal Lancet, which claimed that vaccination shots with a certain mercury compound may be linked to autism. A few years later, however, the finding was completely debunked, and in 2011 the original study was exposed as an elaborate fraud. But in the meantime, many thousands of parents in both the U.S. and the U.K. jumped on the anti-vaccination bandwagon, and, tragically, several childhood diseases began to re-appear. In 2012, measles outbreaks rose to an 18-year high in England and Wales, while in 2011 California experienced its worst whooping cough epidemic in 60 years. In spite of these grim statistics and pleas from health agencies, many parents are still resisting vaccinations for their children.

Just as absurd is the current anti-smart-meter movement. Many in the U.S., Canada, Australia and elsewhere are convinced, without any solid scientific evidence, that smart meters pose a dire threat to health, because of their occasional transmissions of usage data via cell phone networks. Yet even if one stands less than one meter (3 feet) from a smart meter when it broadcasts its data, microwave exposure is 550 times less than standing in front of an active microwave oven, and 1100 times less than holding an active cell phone at your ear.

Cell phone usage itself is thought by many to be dangerous. But in 2010, a 13-nation study commissioned by the world Health Organization found at most a very sketchy and partially contradictory link between cancer risk and heavy cell-phone usage. Along this line, concerns that cell phone usage by pregnant mothers endangers their fetuses are wildly exaggerated.

A related example is the worldwide reaction to the Fukushima reactor accident. This was truly a horrible incident, and we do not wish to detract from the environmental devastation that occurred. Yet no fatalities resulted, and an international panel of experts concluded that the lifetime risk of cancer due to radiation exposure for people living in the vicinity is elevated at most by 1%.

Subsequently, Germany decided to discontinue its nuclear program. Was this decision made after a sober calculation of relative risk and costs between different forms of energy? Or from populist political pressure? This decision inevitably will mean more consumption of fossil fuels, in an era when concern about global warming is, if anything, more acute than ever. And most of the arguments against nuclear power are based on political philosophy rather than science.

Similar remarks can be made about hyped-up fear of genetically modified organisms(GMOs)global warming skepticism, disbelief in evolution, and many other current issues—from why people still smoke to why gun control is impossible in the United States.

We are all susceptible of being swayed by whims of social movements around us, but it is clear that higher-quality education in mathematics and statistics is essential in forging a public mind that is better at assessing relative risk and cost. Indeed, a solid case can be made that a good course in reasoning and statistics should be a required part of a high school education, at least in the developed world and probably in the developing world as well. But better news reporting is also needed from the scientific news establishment. Many of the recent manias would not have gotten off the ground had a more sober-minded press seen through the quasi-scientific smokescreens.

[Added 4 Jun 2013: With regards to the Fukushima accident, a recent study has analyzed levels of radioactivity found in bluefin tuna and other Pacific seafood, and concluded that the amount of radioactivity ingested by eating 124 kg of tuna per year is only half that received by a typical human over the course of a day from a variety of natural and human sources.]

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