HOMO ECONOMICUS IS DEAD:

In an ideal world, people would base medical decisions on an unbiased evaluation of available evidence. But people are often irrational, and many, perhaps most, of their actions are driven more by emotion than facts. [...]

"A child's risk of getting cancer from asbestos insulation in a school building is about one-third the chance of being struck by lightning," Dr. Lisa Rosenbaum wrote last month in the New England Journal of Medicine. "Nevertheless, in 1993, frightened New York City parents agitated for asbestos removal from schools."

Although many experts endorsed containment, not removal, as a saner and safer solution, fear prevailed. Billions of dollars were spent on asbestos removal that should have been spent on education. And removal probably increased -- not decreased -- children's exposure to airborne asbestos. [...]

Sometimes, in fact, more information can heighten people's concerns and prompt them to act in ways unsupported by evidence.

For example, one study used solid data and graphic images to reassure parents that vaccinating children against measles can be lifesaving and is not linked to autism. The effort "not only failed to increase vaccination intent but also cemented some parents' conviction that there is a link between vaccines and autism," Rosenbaum wrote.

"People did not respond as expected," Rosenbaum said in an interview. "Many got even more freaked out."

As shown with Ebola, people are more fearful of things they can't control, however remote the risk may be.

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