How do we know what works? In an uncertain world, full of untested treatments, disputed policies and untried inventions, it should be a pressing question. For an impoverished young tailor named Franz Reichelt, the answer was: we find out the hard way.
In February 1912, on a cold Sunday morning, Reichelt persuaded journalists, a camera crew and a small crowd to watch him demonstrate his new wearable parachute. The official story was that Reichelt would throw a dummy from the first floor of the Eiffel Tower, more than 50 metres up. Reichelt, however, had tipped off journalists that he would make the jump himself. Otherwise, one suspects, there would have been fewer spectators.
The parachute is, as it happens, something of a running joke in evidence-based policymaking. In the Christmas 2003 edition of the British Medical Journal, obstetrician Gordon CS Smith and public health researcher Jill Pell published a systematic review of “Parachute use to prevent death and major trauma related to gravitational challenge”. They noted, with mock sorrow, that “we were unable to identify any randomised controlled trials of parachute intervention” and called for “the most radical protagonists of evidence-based medicine” to organise and participate in a rigorous randomised trial of the parachute.
In case the joke has passed you by, the argument being lampooned is a complaint by advocates of evidence-based policymaking. Many well-established medical practices — along with ideas in policing, criminal justice, education, economics and beyond — have never been seriously tested by the gold standard for evidence: a double-blind, randomised controlled trial (RCT). RCT advocates suggest that this is a scandal. Is it?