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RCT study shows parachutes make no difference when jumping from aircraft

Sometimes Randomized Controlled Trials are not the golden trophies of science that some say they are. (Like yesterday’s Ivermectin study). While some say that nothing less than an RCT will do, actually, sometimes it’s just silly to do one. And all RCT’s will wallow on the rocks of confirmation bias if they try to study something people already know the answer to.

For a long time there were no RCT studies showing benefits from parachutes — yet people continued to use them.  It wasn’t until 2018 that a paper was finally published, surprisingly showing that there was no statistical difference in jumping with or without one from an average altitude of 4,000m.

This satirical paper makes real points about the flaws of the hallowed RCT’s:

  1. It’s easy to design an RCT to show the opposite of the truth.
  2. Reading the abstract of a paper is rarely enough. Reading a news headline, even less so. Details are everything.
  3. RCT’s are not random if the test subjects have opinions and can self-select themselves out of the experiment.

These authors are black-belt professionals at medico-lingo. Those that appreciate the wit will want to read the whole thing rather than just the snippets below (I really can’t do it justice):

Parachute use to prevent death and major trauma when jumping from aircraft: randomized controlled trial

Robert Yeh et al, 2018, British Medical Journal

Parachutes are routinely used to prevent death or major traumatic injury among individuals jumping from aircraft. However, evidence supporting the efficacy of parachutes is weak and guideline recommendations for their use are principally based on biological plausibility and expert opinion. Despite this widely held yet unsubstantiated belief of efficacy, many studies of parachutes have suggested injuries related to their use in both military and recreational settings, and parachutist injuries are formally recognized in the World Health Organization’s ICD-10 (international classification of diseases, 10th revision). This could raise concerns for supporters of evidence-based medicine, because numerous medical interventions believed to be useful have ultimately failed to show efficacy when subjected to properly executed randomized clinical trials.

The researchers were diligent at collecting data which was essentially useless:

Participants were randomized to wear either a parachute (National 360, National Parachute industries …) or an empty backpack (The North Face, Inc, Alameda, CA…). The interventions were not blinded to either participants or study investigators.

We collected data on basic demographic characteristics during screening by using paper forms or the survey app. Characteristics included age, sex, ethnic group, height, and weight. We also collected information on participants’ medical history including a history of broken bones, acrophobia (fear of heights), previous parachute use, family history of parachute use, and frequent flier status.

At the time of each jump, researchers recorded the altitude and velocity of the aircraft, and conducted a follow-up interview with each participant to ascertain vital status and to record any injuries sustained from the free fall within five minutes of impact with the ground, and again at 30 days after impact.

Details are everything:

Results: Parachute use did not significantly reduce death or major injury (0% for parachute v 0% for control; P>0.9). This finding was consistent across multiple subgroups. Compared with individuals screened but not enrolled, participants included in the study were on aircraft at significantly lower altitude (mean of 0.6 m for participants v mean of 9146 m for non-participants; P<0.001) and lower velocity (mean of 0 km/h v mean of 800 km/h; P<0.001).

So the control group with parachutes jumped from 9,000m at 800 km per hour, and participants were more likely to have jumped with backpacks from 0.6m and 0 kilometers per hour.

UPDATE: Before anyone criticizes the trial design, know that the researchers boarded a commercial passenger jet and tried to recruit people for the trial for the 9000m jump with and without a parachute, but were unable to get any participants to sign on to that randomized intervention. However they were able to recruit participants for 0.6m jump with and without said intervention.

Obviously the design of the experiment was entirely fair and even handed, it was just that the participants held strong preconceived and prejudicial conclusions, without evidence, and selected themselves out of the experiment.

The primary efficacy analysis tested the hypothesis that parachute use is superior to the control in preventing death and major traumatic injury. Based on an assumption of an average jump altitude of 4000 meters (typical of skydiving) and the anticipated effect of impact with the Earth at terminal velocity on human tissue, we projected that 99% of the control arm would experience the primary outcome at ground impact with a relative risk reduction of 95% in the intervention arm. A sample size of 14 (7 in each arm) would yield 99% power to detect this difference at a two sided α of 0.05

 

RCT on Parachutes

No deaths were recorded from people jumping from planes with backpacks.

Conclusions Parachute use did not reduce death or major traumatic injury when jumping from aircraft in the first randomized evaluation of this intervention. However, the trial was only able to enroll participants on small stationary aircraft on the ground, suggesting cautious extrapolation to high altitude jumps. When beliefs regarding the effectiveness of an intervention exist in the community, randomized trials might selectively enroll individuals with a lower perceived likelihood of benefit, thus diminishing the applicability of the results to clinical practice.

The study also has several limitations. First and most importantly, our findings might not be generalizable to the use of parachutes in aircraft traveling at a higher altitude or velocity.

Should our results be reproduced in future studies, the end of routine parachute use during jumps from aircraft could save the global economy billions of dollars spent annually to prevent injuries related to gravitational challenge.

Confirmation bias (and ethics) means both patients and doctors are likely to opt not to take part in an RCT when they believe the intervention is particularly useful. This means many RCT trials are filled with people at low risk who may not benefit or miss out much either way. True RCT’s may be very useful but they are inherently cruel.

 

10 out of 10 based on 87 ratings

75 comments to RCT study shows parachutes make no difference when jumping from aircraft

  • #
    Ronin

    You have to feel for those chosen to test the theory of jumping without a parachute.

    90

  • #
    David Maddison

    Very good article.

    100

  • #
    David Maddison

    As a matter of interest, here is a list of the highest falls people are known to have survived without a parachute. Not satire.

    https://www.statista.com/chart/19708/known-occasions-where-people-survived-falls/

    110

  • #

    It’s a beautiful example of how the concept of averages is misused and abused. Averages are often used when range is far more appropriate.

    Valid: the average width of a Hydrogen atom.

    Invalid: the average height of all aircraft currently flying at their maximum altitude.

    90

    • #
      Binny Pegler

      There’s and old yarn about the pith helmet being issued to the British forces in India. Because of a report stating that 50% of casualties for the previous year had been from sun stroke…. The other causality for that year had been from a tiger attack. But the person who issued the report was selling pith helmets, not tiger repellent.

      170

    • #
      Deano

      My own extensive study (I just made this up) shows that 97.64% of fatal road crashes over the past 50 years involve drivers with valid drivers licenses. Yes – you far safer driving without a license.

      80

  • #
    Annie

    🙂 🙂 🙂

    70

  • #
    David Maddison

    Official doctrine is that ivermectin is only a “horse dewormer”.

    Ivermectin is a possible treatment for Japanese Encephalitis which is caused by a flavivirus.

    “Ivermectin is a potent inhibitor of flavivirus replication specifically targeting NS3 helicase activity: new prospects for an old drug”

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC38881/5/

    Japanese Encephalitis is already in Australia and is regarded as incurable and has up to 30% mortality.

    Japanese Encephalitis in Australia:

    https://www.health.vic.gov.au/health-advisories/japanese-encephalitis-virus-detected-in-victoria

    I will be interested to see if the “horse dewormer” is allowed to be used to treat this deadly and incurable disease or will it be regarded as “too dangerous”?

    380

    • #
      Ross

      At leat in Australia IVM has approval for other human uses ( scabies etc), so you would think that would give it an easy pass card for JE. But it didn’t matter with COVID. The TGA just followed blindly the FDA exclusions. If there is no expensive treatment in the pharm pipeline for JE, then there is a slim chance that IVM could be used for JE. Because JE is possibly only a small market , Big Pharma may not care less.

      120

  • #
    Simon Thompson.

    It could be improved though. What about selecting dodgy endpoints like highlighting the facts that parachutes increase the risk of sprained ankles. Like the fact that the government notices “reduced hospitalisation” as a marker of severity whilst ignoring infection rates (gone up 2500x) “Vid death rate (10x increase), and excess all cause mortality in the working age group (10-40%)

    90

  • #
    David Maddison

    Unless you are one of the people who survived the unlikely event of surviving a fall without a parachute, NOT using a parachute usually results in a zero hospitalisation rate. In contrast, emergency parachute users will often require medical treatment for injuries such as sprained ankles, minor cuts and bruises etc..

    170

  • #
    Sambar

    “This satirical paper makes real points about the flaws of the hallowed RCT’s:

    It’s easy to design an RCT to show the opposite of the truth.”

    Slightly off topic but it does fit with the way information is gathered.

    Had to do a PCR test as a prerequisite for minor medical work. Was asked all the normal questions, name, address, aboriginal or Torres Strait, country of birth etc.

    The one question I was NOT asked was my vaccination status. So the gathering of information is designed to purposely exclude whether more, less or no detectable difference between unvaccinated, single, double or triple vaccinated people reflected in positive tests. Personally I would have thought that this was the most important question.

    270

    • #
      Bruce

      POLITICAL “science” ROOLZ!!

      Lysenko LIVES!!

      70

    • #
      PeterPetrum

      Figures that I saw recently from the UK NHS between week 32 and week 35 in 2021 show that in the age groups from 40 to 79 the rates of infection are significantly greater in those who have been double vaccinated than those who have had no vaccinations. Looks like it is the unvaccinated who are at greater risk from the vaccinated in those age groups. The rates were significantly lower in the under 18s to 39 years old.

      120

    • #
      Brock

      Earlier in the Plandemic they had varied the Cycle Threshold (CT) of the PCR test depending on vaccination status, the rationale being that vaccinated individuals will be carrying the Coronavirus spike protein in their nasal passage, so the PCR test was detuned from 40-45 cycles (CT) for the unvaccinated (guaranteed albeit ‘false’ positive result) to 16 (CT) for the vaccinated. (guaranteed negative result) . By this mechanism it is easier to demonstrate that vaccination prevented infection from COVID-19 (tongue in cheek).

      However then WHO was under scrutiny for using the very high CT of 40 knowing that this results in about 99% false positives (even Fauci coinceded that), so as the Plandemic developed they reduced the CT and at that point it became a potential legal liability to record someones vaccinaton status – hence best to remain silent. There should be a trial of the Medical bureaucracy and their regulatory mates before a jury of peers.

      40

  • #
    Gnrnr

    Damn that was a great read from that paper. Very funny.

    100

  • #
    max

    What is truth?
    The future of civilization rests on the answer to that question. Every civilization rests on a conception of truth. Its life is this faith in action. It prospers or falls in terms of its conception of truth.

    Thomas Kuhn’s 1962 monograph, The Structure of Scientific Revolutions implied, but refused to say openly, that there is no universal truth. There are only opinions that are dominant inside specific academic guilds ( establishments ). This opinions change over time.

    Richard P. Feynman:

    “Scientific knowledge is a body of statements of varying degrees of certainty — some most unsure, some nearly sure, none absolutely certain.”

    Deciding who we should trust is one of the most important life skills.

    The minute you deny that God is God, then you deny the coherence of reality. Then things don’t hang together,

    without God, but very quickly in terms of their own thinking, the world is gone and truth is gone. By denying God, they have denied everything.

    40

  • #
    Grogery

    I suggest we do a new similar study to see if the results differ from the study above.

    Participants:
    1000 x professional skydivers with their parachutes.
    1000 x Australian politicians with empty backpacks.

    All jump from the plane at an altitude of 9000 metres, travelling at a speed of 800 km per hour.

    I’ll be happy to help tally the results.

    170

    • #
      Graeme No.3

      Don’t stand underneath.

      80

    • #
      MarkMcD

      Good test. Pollies would likely have a high survial rate as the CO2 would cause their backpacks to inflate with the hot air and lower them gently to the ground!

      120

      • #
        sophocles

        Quite a few test subjects would suffocate from air shortage — or sustain damage — from air deprivation if jumping from 27200 feet (9000metres).]

        There’s not a lot of air that high up at all, at all, at all🙂.
        (approx 5psi).

        00

    • #
      yarpos

      Exiting an aircraft at 800km/hr would be painful and extremely difficult. Thats way out of skydiving territory and into ejection seat world.

      70

  • #
    Dave

    Jo, you’ve again torn the veil away from the leftist controlled cabal of scientific institutions !.
    You’ve used a satirical trial to prove that peer review works, could you now submit your own evidence to the real world?.

    41

  • #
    Simon Thompson.

    The best statistical slight is using relative risk.
    If my absolute risk of surviving ‘Vid is 99.997%
    JabJabJab improves the absolute risk by 0.001 % (or actually increase the risk)
    (As JabJabJab causes deaths in and of itself)

    How can the Misleadia ignore 2500x case rates and 10 x vid mortality rate notwithstanding
    the obligatory NodNodWinkWink ignoring JabJabJab morbidity/mortality.

    A lot of money is being directed towards killing people.

    160

  • #
    Ian

    “1000 x Australian politicians with empty backpacks.”

    But which politicians? A very recent survey by Roy Morgan shows the least trusted politicians who would be first in line are

    1. Scott Morrison. 2. Peter Dutton, 3. Barnaby Joyce. 4. Pauline Hanson .5. Craig Kelly. 6. Dominic Perrottet
    7. Angus Taylor. 8. Michaelia Cash. 9. Josh Frydenberg. 10. Matthew Guy

    The most trusted politicians who would not be in the line up are

    1. Penny Wong. 2. Anthony Albanese. 3Tanya Plibersek. 4. Mark McGowan. 5. Jacqui Lambie.
    6. Gladys Berejiklian. 7. Adam Bandt.

    126

  • #
    Peter Fitzroy

    How could it an RCT when the control group jumped form a plane which was stationary on the ground while the while the test group were flying etc. it might be fun, but it is not, and can never be an RCT

    021

    • #
      Hanrahan

      The left have no sense of humour, ergo they don’t meme well.

      150

      • #
        David Maddison

        The left have no sense of humour, ergo they don’t meme well.

        https://unherd.com/2021/08/why-the-left-cant-meme/

        Why the Left can’t meme

        ‘Woke comedy’ will never compete with the despair of the online Right

        “No great movement designed to change the world can bear sarcasm or mockery, because they are a rust that corrodes everything it touches.” So wrote the Czech writer Milan Kundera in his novel The Joke.

        Humour has long been a magic ingredient in unlocking political change. In the medieval court, jesters had an almost unique privilege in being able to tell the monarch what he didn’t want to hear, and were often tasked with presenting bad news. In totalitarian regimes humour was a daily act of undermining the regime, to the extent that on Stalin’s death 200,000 of the Gulag’s 2.5m population were there for telling jokes.

        [..]

        SEE LINK FOR REST

        50

        • #

          Peter, the researchers boarded a commercial passenger jet and tried to recruit people for the trial for the 9000m jump with and without a parachute, but were unable to get any participants to sign on to that randomized intervention.

          However they were able to recruit participants for 0.6m jump with and without said intervention.

          Obviously the design of the experiment was entirely fair and even handed, it was just that the participants held strong preconceived and prejudicial conclusions, without evidence, and selected themselves out of the experiment.

          [Thanks Peter, I’ve just added this note to the post. Useful question. – Jo]

          60

      • #
        TedM

        “The left have no sense of humour, ergo they don’t meme well.” And they don’t understand the subject either.

        40

      • #
        another ian

        H

        Looked at the other way – that is why they meme extremely well

        10

    • #
      PeterPetrum

      Peter, that is the point of the whole research project but, of course, you missed it.

      60

    • #
      Kalm Keith

      Ask the Koalas to assess it.

      10

  • #
    Hanrahan

    There is a gem of truth there:

    True RCT’s may be very useful but they are inherently cruel.

    To do an RCT on IVM with half getting the placebo WOULD be cruel and unethical.

    80

  • #
    Vlad the Impaler

    As was pointed out in an earlier thread, one does not need a parachute to skydive.

    You only need a parachute if you intend to skydive again.

    230

  • #
    TdeF

    For those who missed it, the control group with parachutes is as dangerous as the randomized sample is safe

    “the control group with parachutes jumped from 9,000m at 800 km per hour”

    This is higher than Everest at full speed for a pressurized passenger jet and outside at 20% of normal. Try opening the door without explosive decompression. The value of a parachute is zero.

    60

    • #
      yarpos

      High altitude jumps arent done from pressurized aircraft. Everyone breaths from an O2 supply above 12k or so (varies by country)

      In the US you can do psuedo military style tandem HALO jumps for expensive fun, exiting from 25k to 30k ft.

      The current world record sydiving formation (400 people) was done from 25k over Thailand from 5 x Hercs.
      Thats a lot of O2 plumbing.

      Most of parameters in the satire piece are within the realm of reality except for the 800km exit speed. That aint happening for skydiving.

      60

      • #
        TdeF

        It’s all in James Bond movies like most extreme sports, sure, but not my point. The Control group are not jumping out of a Cessna. And no one willingly jumps out of anything at any altitude at 800km/hr.

        50

        • #
          yarpos

          mmmmm quite the reference point James Bond movies. You really think they accurately portray anything? Plenty of people have exited aircraft at 800km+ just not skydivers. Its better than going in.

          30

          • #
            TdeF

            James Bond movies have always been amazing for their stunts at the edge of technology. In Diamonds are forever they showed the Space Shuttle take off and moon rover before they were public knowledge and in hindsight, they were guessing. And no end of aerial adventures with aircraft and parachutes at the extreme end of the sport or military. Like the Halo jump into water. Even parachutes from a burning 747. But it is entertainment, not a documentary.

            00

    • #

      Don’t worry, that was part of the joke.

      110

  • #
    MarkMcD

    Gavitationally challenged!!! Gotta love that,

    I wonder if this passed peer review?

    40

  • #
    MarkMcD

    Something that may have been in the paper (which I have not read) that could have made it better is to state the participants jumped from an average height of 2000m. i.e. w/chutes from 4000 and w/o from 0m.

    Or they could have even recorded height above sealevel of the airport where the non-chutes performed.

    60

  • #
    Russell

    There’s something vaguely similar about this and political polls that try to estimate a party or candidate chances of attaining votes.
    RCT’s Polls are not random if the test subjects punters have opinions and can self-select themselves out of the experiment poll.”
    And no amount of additional polling can compensate when a politically-smart segment of punters are universally “not interested in polling”.
    Because they have learned that the questions are always biased to achieve “the designed result”.

    70

  • #
    Ross

    The proclamation that RCT’s are the “gold standard” in proving efficacy of pharmaceuticals and allied products eg Vaccines was just the ultimate goal of the pharmaceutical industry to exclude small players. Because to run an RCT costs some serious $. So, only companies with huge budgets can run them. Which is Big Pharma. The only other way to fund these trials would be via substantial govt funds or some philanthropic billionaire. Thats simply what happened to IVM, HCQ and all the other 30 odd possible products that could have been used to help in the treatment of COVID. There’s no profit margin in them, so no particular company has any desire to fund an RCT. But, anyone who has done any clinical scientific trials knows that observational trials, when supervised and documented professionally and repeated in many environments are the equal if not better data providers than RCT’s. Hence, the impasse with FDA, TGA and all the other regulatory authorities around the world who can be either directly funded by Big pharma or rotate personnel between them. So, in reality COVID wasn’t really an “emergency” at all. Because if it was an emergency, those RCT requirements by the regulatory authorities could have been bypassed by political decree. Hence, the reason a lot of us are conspiracy theorists and don’t believe the BS.

    91

    • #
      David Maddison

      Agreed. Opponents of the off-label, off-patent, inexpensive and known safe drugs regularly mocked any observational trials that had been repprted and refused these drugs to be considered, even before any so-called “vaccine” was available.

      80

      • #
        Ross

        Yesterday, I learnt my brother in law (70yo) has contracted shingles. There appears to have been an increase in all sorts of ailments since the vax program started. Most notably shingles. By absolute miracle there’s a new drug for Shingles!!! The BIL has to take 6/day. Isn’t that an amazing coincidence? Bit like the medical industry had no qualms about blood clotting with eg AZ vaccine after the arrival of some new miracle anti clotting medications in 2021. Another absolute amazing coincidence.

        80

  • #
    R.B.

    Do you need a placebo when a disease makes you so ill that positive thinking just aint going to be enough, while you have millions who have caught it and know the rate of severe illness? Even if death rates and severe illness are decreasing, a sample of thousands in the most vulnerable to becoming seriously ill should show whether it’s worth taking, especially if safe enough to be sold over the counter and cheap.

    And it was done by states ignoring US experts, successfully.

    40

  • #
    John Connor II

    I asked my parachute instructor what happens if it doesn’t open.
    He said you’re jumping to a conclusion.

    Pope Francis, Donald Trump, Joe Biden, and a little boy are crossing the Atlantic on an airplane when the engines fail.
    They only find three parachutes.
    Donald Trump grabs the first parachute and jumps out of the plane saying, “The world needs a great person like me!”
    Joe Biden grabs a parachute and says, “I need to help make choices for our world”, so he jumps off the plane.
    At this point, the Pope and the little boy are on the plane.
    The Pope says to the boy, “take the last parachute, I am too old and I’m going to die soon one day.”
    “Actually there are two left. Joe Biden took my backpack.”

    130

  • #
    another ian

    One could do an equivalent spoof of the entire Peking Pox saga along those lines.

    “The Bloom Is Off the Ruse as New Zealand Drops Almost All COVID Restrictions, Including Vax Passports, Mandates and QR Codes
    March 23, 2022 | Sundance | 30 Comments”

    https://theconservativetreehouse.com/blog/2022/03/23/the-bloom-is-off-the-ruse-as-new-zealand-drops-almost-all-covid-restrictions-including-vax-passports-mandates-and-qr-codes/

    20

  • #
    Macspee

    Is anyone looking at the increas in heart problems and their vaccination types and times?

    40

  • #
    Ed Zuiderwijk

    You gotta love the empty backpack (North Face).

    40

  • #
    Gerald the Mole

    Many years ago in the UK there was TV series called Brass. In it a medical doctor stated that all serious injuries experienced by people who fell off ladders happened in the height range from the ground of 0-9″.

    30

  • #
    UK-Weather Lass

    The acronym used in the paper – PARACHUTE – is just one part of the fun of reading the whole.

    30

    • #

      I particularly liked their joke

      “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.”

      A crossover trial means those that jump with a parachute in the first half, do the opposite in the second half…

      30

  • #
    Lewis

    I feel an April the first experience coming on.

    30

  • #
    George McFly......I'm your density

    Brilliant article Jo.

    20

  • #

    You can very well descend from 4000 m without a parachute and by car!
    On the other hand, we have never tested the dropping of a car at 4000 m!

    00

  • #
    Yonason

    The latest data from OSHA show that two parachutes are more effective than one, unless you are using the industry standard N95 chute, in which case one is sufficient. //s//

    00