Skeptics wanted for participation in double-blind study

[Mercutio]

A well-known "safety device" which has been in use for hundreds of years, has never actually been tested in double-blind conditions. Anecdotal evidence is not good enough! Smith & Pell (2003) (http://bmj.bmjjournals.com/cgi/content/full/327/7429/1459?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=parachute&andorexactfulltext=and&searchid=1141068034599_17995&FIRSTINDEX=0&sortspec=relevance&resourcetype=1) review the (lack of) literature, and make recommendations.
As with many interventions intended to prevent ill health, the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomised controlled trials. 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.The parachute is used in recreational, voluntary sector, and military settings to reduce the risk of orthopaedic, head, and soft tissue injury after gravitational challenge, typically in the context of jumping from an aircraft. The perception that parachutes are a successful intervention is based largely on anecdotal evidence. Observational data have shown that their use is associated with morbidity and mortality, due to both failure of the intervention1 2 and iatrogenic complications.3 In addition, "natural history" studies of free fall indicate that failure to take or deploy a parachute does not inevitably result in an adverse outcome.4 We therefore undertook a systematic review of randomised controlled trials of parachutes.

...and my favorite part:Contributors: GCSS had the original idea. JPP tried to talk him out of it. JPP did the first literature search but GCSS lost it. GCSS drafted the manuscript but JPP deleted all the best jokes. GCSS is the guarantor, and JPP says it serves him right.
Funding: None.

Competing interests: None declared.

Ethical approval: Not required.

Yes, there is a serious element to this paper, and a point that is relevant to a good many claims made around here. So don't tell me I have missed the point.

[Arkan_Wolfshade]

Actually, the safety of parachutes could be succesfully tested in a double-blind study be using a bunch of Busters (1). Have people pack some parachutes, and some "placebo"chutes and have others attach them to the Busters, and throw them out of an airplane.

Why do I suggest this? Because even someone as obvious as parachutes can be tested and their validity confirmed.


(1) Good episode for Mythbusters perhaps?

[brodski]

although not properly blinded, there have been many randomized trials of this device. :p
More seriously, there have also been many years of military tests.
The authors of the paper do however miss the point, where the outcomes is not subject to observer bias blinding is less important. the problem is, the authors of this study go on to use it as an attack on evidence based medicine, where observer bias is important.
A witty argument from the woos, but one with few lessons for skeptics.

[T'ai Chi]

A well-known "safety device" which has been in use for hundreds of years, has never actually been tested in double-blind conditions. Anecdotal evidence is not good enough!

Um, using observational data, or it not being double blind, randomised, placebo controlled, or in a crossover trial, is not the same as it being anecodtal.

[J. Arthur Hastur]

Um, using observational data, or it not being double blind, randomised, placebo controlled, or in a crossover trial, is not the same as it being anecodtal.

I would have said that, but there you go.

[Dr Adequate]

the problem is, the authors of this study go on to use it as an attack on evidence based medicine ... A witty argument from the woos, but one with few lessons for skeptics. No, it's a joke.

You should have realized that when you typed the words "a witty argument from the woos". I mean, how likely is that?

[brodski]

No, it's a joke.

You should have realized that when you typed the words "a witty argument from the woos". I mean, how likely is that?
And what is the point of the joke? That there are some truths so obvious that three is no need to test them.
Now, who has an interest in having their "treatments" accepted, without testing?
Read the BMJ rapid responses if you don't think that the article is playing to the woos.

[ClusterBoy]

Read the BMJ rapid responses if you don't think that the article is playing to the woos.

pandering to the woos? the 2nd rapid repsonse is by one E.J. Woo, who appears to be unfortunatly monikered. i googled her, and she's real. And quite a good scientist by the look of it.

[Dr Adequate]

And what is the point of the joke? That there are some truths so obvious that there is no need to test them. Not quite. Parachutes are tested. Just not double-blind.

Now, who has an interest in having their "treatments" accepted, without testing? Woos. However, the efficacity of woo medicine is not "so obvious that there is no need to test ".

However, sometimes the effects of a real medicine, such as insulin, are so that obvious; a medicine such as insulin [i]may be so sucessful that a double blind trial would be unecessary and (if the subjects were human) unethical.

This is not, of course, to assert that insulin hasn't been tested. It has --- by giving it to diabetics.

[Mercutio]

Sometimes the self-evident truths that lead to very common medical procedures are worth poking holes at. Knee surgery provides us with an example. (http://www.bcm.edu/pa/kneesurgery.htm)

Link to original study. (http://content.nejm.org/cgi/content/abstract/347/2/81)

[CFLarsen]

Blonde preparing for her first parachute jump.

Blonde: "What if I pull the string and the parachute doesn't open?"

Instructor: "Then you pull that string. It's for your reserve parachute."

Blonde: "What if that doesn't work either?"

Instructor: "Oh, come on! You'll be 10 feet above ground! You can fall 10 feet...."





[True Anecdote]

Girl telling her friends that she is going on her first parachute jump.

Friends: "What if the parachute doesn't open?"

Girl: "Then, I have my reserve parachute."

Friends (pulling her leg): "What if that doesn't open either?"

...long pause...

Girl: "...But it has to!!!"

[/True Anecdote]

[articulett]

Who would be the controls and how would they be equipped with fake parachutes? Data is often accumulated through retrospective evaluation. Let's compare those who fall from on high (say those who jumped from the WTC) without parachutes and those who had them. Of course, parachute effectiveness is not 100%--which is why there is a back up...I'm sure studies could also be done to determine the risk of injury/death per jump with and without a backup... Aeronautical safety tends to be of the "learn from our mistakes" and lets think of all the things that could go wrong type--not the double blind type. Double blind studies are generally done for medical procedures are generally reserved for cases when lack of treatment is unlikely to lead to harm. We can't make a flat earth to determine that the earth is not flat though I'm sure we could scrounge up a few woos, ignoramuses, and the like who had no predetermined belief on the subject.

[articulett]

Perhaps Smith and Pell would like to volunteer for studies to determine whether helmets protect one from head injury should a sharp blow to the noggin occur.

[Deetee]

Sometimes the self-evident truths that lead to very common medical procedures are worth poking holes at. Knee surgery provides us with an example. (http://www.bcm.edu/pa/kneesurgery.htm)

Link to original study. (http://content.nejm.org/cgi/content/abstract/347/2/81)

Merc, you may have missed the thread (http://forums.randi.org/showthread.php?t=51271) on this in the science forum a few weeks back.

There was a UK TV programme that looked at this study. The presenter was blown away by the concept that "placebo was as good as surgery", concluding there was some magical inner healing power we all posess. The article actually is explicit that "surgery is no better than placebo" and is therefore perhaps not worth performing. The presenter did not discern the difference, bless her cotton socks. (The surgery was not even "surgery", merely a joint wash out through a key hole incision).
Unfortunately the presenter is a scientist, Professor Sykes from Bristol University. A sad day for scepticism and critical thinking all round. She even happily pronounced: "I used to be a sceptic..."

:bwall