Without evidence of benefit, an intervention should not be presumed to be beneficial or safe.

- Rogue Medic

Narrative Fallacy I

In looking at the research on the ability of mechanism to predict actual severity of injury, we first have to look at some of the problems with research. One of these problems is the use of narrative fallacy to try to explain things that the research has no ability to explain.

What is narrative fallacy?

Narrative fallacy is the need to put information into a narrative, or story, to explain the unknown. Although, if we are explaining the unknown, it cannot be unknown. The problem is that we delude ourselves into believing that we understand what we are explaining. We convince ourselves that we know the unknown. A study comes out that shows that Drug X has a positive effect on Disease Y, so somebody feels the need to give explanation Z.

Why?

To satisfy that need for an explanation. We need to ignore the explanations as much as possible.

But we need to know why we are giving a treatment!

We give a treatment because research shows that it is effective for a specific condition. Everything that has not been shown to be effective is experimental. The explanation is not important. The explanation is often wrong and will probably be revised significantly, if not completely reversed.

The creation of a hypothesis is a necessary part of the scientific method. It is a way of generating testable ideas. We should not apply it to the results of experimentation, except to create more hypotheses to be tested.

Without the scientific method, we have magical thinking. The scientific method is the best way we have of protecting ourselves from the mistakes of magical thinking. Magical thinking is believing that something is happening by some mechanism that sounds good, may even make a lot of sense, but it is untested.

Explanations make it so that we feel better about what is happening. We feel that we have some ability to control things. Stories also help us to remember information. Try remembering a bunch of random information. It is difficult to remember random information. Put that information into a story and you will find that your ability to remember the information increases dramatically. The story doesn’t even have to be relevant. This is why we use mnemonics. They are memory aids.

One of the old mnemonics for ACLS (Advanced Cardiac Life Support) was Shock, shock, shock; Everybody shock; Little shock, Big shock. This was a way of memorizing the beginning of the Ventricular Fibrillation/Pulseless Ventricular Tachycardia algorithm. Shock, shock, shock = shock 3 times, or defibrillate at 200 joules, 200 – 300 joules, then 360 joules. Everybody shock = the E was a reminder that Epinephrine was the first drug after the initial shocks, then shock once again. Little shock = the L was a reminder that the first antiarrhythmic drug was Lidocaine, then we shocked again. Then you needed to remember to repeat epinephrine and a shock. You might give more lidocaine, or you might move on to the next antiarrhythmic – Big shock = the B was a reminder that the next antiarrhythmic drug was Bretylium.

These were just something that somebody thought up. They were just to help some people remember the order of drugs, but not the doses. The drugs from the mnemonic are mostly gone from the treatment of Ventricular Fibrillation/Pulseless Ventricular Tachycardia.

Why?

They weren’t based on real science, just expert opinion. For the time, expert opinion was the way to go. Now we have done quite a bit of research on these drugs and bretylium is not even used any more. Lidocaine is only used by places that do not use amiodarone. Epinephrine is still used, but not in the high doses that used to be encouraged. None of the drugs are supported by research that shows more patients surviving with a functioning brain, but we are so caught up in the narrative fallacy of epinephrine to get the heart going and antiarrhythmics to make the bad rhythms go away, that we continue to use these ineffective drugs. As we become more aware of the gaping holes in the narrative fallacy, we modify, or remove, the errors. This is how science progresses. We stumble along from one experiment to the next, with the occasional major revision.

The drugs are no longer the main focus, since they do not work. Still, in science politics does have a role. Some refuse to let go of the idea of a wonder drug of resuscitation. But this is a great example of the narrative fallacy.

How?

The drugs do not work, but there are wonderful scientific explanations of the way they work. Since they do not work, this is just wishful thinking. It may be great to help you remember the order of treatments, but you will have to learn some other mnemonic later, because they will eventually accept that the research is just not there to support using these drugs in cardiac arrest.

If you want to read the current narrative fallacy, the link at the bottom will give you all of the current explanation of how the drugs work. The older versions of ACLS explanations carry the narrative fallacy from that time period. The next revision will carry the new and improved narrative fallacy. At least the AHA (American Heart Association) starts out by admitting this lack of understanding in the ACLS text. Too many of the instructors just seem to use the algorithm charts, which do not include the following statement.

For victims of witnessed VF arrest, prompt bystander CPR and early defibrillation can significantly increase the chance for survival to hospital discharge. In comparison, typical ACLS therapies, such as insertion of advanced airways and pharmacologic support of the circulation, have not been shown to increase rate of survival to hospital discharge.[1]

Stories are great – as long as we realize that they are fiction. Even if printed in the most reputable scientific journal, they are not the truth. They are an approximation of how the current research might be explained. Science is not etched in stone. Science is constantly changing. Not every change is progress, but cumulatively there is tremendous progress.

Narrative Fallacy –

Narrative Fallacy I

How did this happen? – Research

Narrative Fallacy II

CAST and Narrative Fallacy

C A S T and Narrative Fallacy comment from Shaggy

Some Research Podcasting Comments

Shaggy Comments on Some Research Podcasting Comments.

Spine Immobilization in Penetrating Trauma: More Harm Than Good?

EMS EdUCast – Journal Club 2: Episode 43

Education Problems, Autism, and Vaccines

Footnotes:

[1] (Circulation. 2005;112:IV-58 – IV-66.)
© 2005 American Heart Association, Inc.
2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care
Part 7.2: Management of Cardiac Arrest

Introduction

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Trackbacks

  1. […] attempts at explaining their results wander into narrative fallacy, which I have written about here, here, here, here, here, here, here, here, here, and […]

  2. […] wrote Narrative Fallacy I before Paramedicine 101 was started. You can read it at Narrative Fallacy I. The brief explanation of narrative fallacy is that a narrative fallacy is something that takes the […]

  3. […] Fallacy I Fri, 24 Oct 2008 12:51:49 +0000 By Rogue Medic Leave a Comment In looking at the research on the ability of mechanism to predict actual severity of injury, we […]

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