Few scientists question the usefulness of randomized controlled trials in assessing the efficacy of medical interventions. Those who argue for more evidence-based medicine frequently highlight the importance of randomized controlled trials, and a particularly strict wing of these evidence-based medicine adherents argues that the only truly evidence-based interventions are those that have been proven safe and effective in randomized controlled trials. An amusing send-up of this militant camp by Smith and Pell was published in 2008 in the British Medical Journal: Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials.
The authors searched the literature for such trials, but alas, "were unable to identify any randomised controlled trials of parachute intervention." As if their feelings were not yet clear, they concluded, "Advocates of evidence based medicine have criticised the adoption of interventions evaluated by using only observational data. We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute." Ouch! I found the "crossover" part of the design especially harsh (or amusing).
A recent event brings hope that Smith and Pell's search for a randomized controlled trial of parachute intervention might one day come to fruition, though such a trial will likely never be placebo-controlled. On 23 May 2012, stuntman Garry Connery intentionally jumped out of a perfectly functioning helicopter flying 2400 feet above the ground without a parachute. Mr Connery landed safely some 50 seconds later on a runway of stacked cardboard boxes. He wore a specially designed "wing suit", and upon landing safely told reporters, "My calculations obviously worked out and I'm glad they did." Well done Mr Connery! But readers: please don't try that at home!