Have you ever wondered if using a parachute when jumping out of a plane has actual medical benefits? In 2017, 24 skydivers died in the US 一 half of them due to parachute malfunctions. While most of us accept that parachutes are life-saving equipment, there is little medical evidence to support their use.
In 2003, The BMJ published a review on “Parachute use to prevent death and major trauma”. The article concluded that “the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomized controlled trials”. But the authors were actually trying to make a different point: while proponents of evidence-based medicine claim that interventions should be based on scientific testing, sometimes carefully controlled testing doesn’t make sense.
Imagine what a randomized controlled trial for parachute use would look like: a control group would be asked to jump out of a plane without a parachute, while the test group would be given this presumably life-saving equipment. Who would even agree to participate in a study that risky? This year, we got our answer.
In 2018, The BMJ published a new study on parachute use – this time using a randomized controlled trial. Aircraft passengers were asked if they would be willing to jump from the plane一at its current altitude and velocity一 while randomly selected to wear either a parachute or an empty backpack. Twenty-three passengers agreed to participate.
The Result: Parachute use did not significantly reduce death or major injury when jumping from aircraft. 一 That shouldn’t be a surprise, because participants in this particular study were jumping from a stationary aircraft, on the ground.
Once again, the study was designed to prove something else: controlled trials rely on willing participants who make judgements based on pre-existing beliefs. Though the researchers tried to recruit participants in-flight, none agreed to jump from several thousand feet without a parachute. Further, the main finding of their research, “parachute use did not significantly reduce death or major injury”, was misleading and failed to provide the context (that the aircraft was on the ground) needed to accurately understand their conclusion.
While both studies are a bit tongue-in-cheek, they illustrate a widespread problem with research today: far too many studies and surveys forgo common sense.
Marguerite Kinne is a Research Specialist at NowSourcing.