Researchers Show Parachutes Don't Work, But Th... - CLL Support

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Researchers Show Parachutes Don't Work, But There's A Catch

AussieNeil profile image

I wonder if this was a double blind test? :)

Research published in a major medical journal concludes that a parachute is no more effective than an empty backpack at protecting you from harm if you have to jump from an aircraft.

But before you leap to any rash conclusions, you had better hear the whole story.

The gold standard for medical research is a study that randomly assigns volunteers to try an intervention or to go without one and be part of a control group.

For some reason, nobody has ever done a randomized controlled trial of parachutes. In fact, medical researchers often use the parachute example when they argue they don't need to do a study because they're so sure they already know something works.

Cardiologist Robert Yeh, an associate professor at Harvard Medical School and attending physician at Beth Israel Deaconess Medical Center, got a wicked idea one day. He and his colleagues would actually attempt the parachute study to make a few choice points about the potential pitfalls of research shortcuts.


In all, 23 people agreed to be randomly given either a backpack or a parachute and then to jump from a biplane on Martha's Vineyard in Massachusetts or from a helicopter in Michigan.

Relying on two locations and only two kinds of aircraft gave the researchers quite a skewed sample. But this sort of problem crops up frequently in studies, which was part of the point Yeh and his team were trying to make.

Full story:

In summary: It's far too easy for scientists who have already anticipated the outcome of their research to cherry-pick patients and circumstances to achieve the results they expect to see.


"It's a little bit of a parable, to say we have to look at the fine print, we have to understand the context in which research is designed and conducted to really properly interpret the results," Yeh says. Scientists often read just the conclusion of a study and then draw their own conclusions that are far more sweeping than are justified by the actual findings. (My emphasis)

An important lesson for when you next read a report that claims substance X eliminates cancer. What was actually tested in the source paper behind the report? Is the cancer CLL or at least a B-lymphocyte cancer? Is the research based on testing cell cultures in a test tube (in vitro) or in a living subject (in vivo), Is it a mouse model study or was the trial done on human subjects and much more...


Photo: Fog droplets on veldt grass

11 Replies

Some writers for newspapers should read this.!

How many times do we read of a NEW wonder drug.


PaulaS profile image

Amazing photo, Neil... :-)

Heard about this on radio in car other day. Thanks for posting! Forgot to read when I got home.

cllady01 profile image

Good guide, Neil, thanks. And love the photo.

Cllcanada profile image
CllcanadaTop Poster CURE Hero

Amazing droplets Neil..thanks... oh the article is good too...!

~chris 🇨🇦

It's why it's called Medical Practice - sometimes more an Art than a Science often quoted. Communication is the key! Nice article -

Love the water droplet photo!

Thanks, Neil. Nice pic. Wish I had a veldt to go to!

So true. I see it frequently in nutrition studies on mice given who knows what, or cherry-picked population studies, to prove meat or fat is bad and a low carb diet will kill you.

Also, I love the photo!

Great article!

Merry Christmas to you and everyone you love Neil!

Thx for keeping HU safe.

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