Remember that if 10 treatments are being tried at once, you can divide the pool of participants so that only a smallish percentage are part of the control group.
Now, there are any number of reasons someone might be rejected from the trial. If that happens, the company isn't going to just freely give them the drug anyway, because that wouldn't provide scientifically valid data. Also, no one would enroll in a trial (which carries the potential of getting the placebo) if they could get the treatment outside the trial.
https://astralcodexten.substack.com/p/book-review-from-overs...
> If your lungs can’t breathe well, doctors can put you on a ventilator, which forces air in and out. It’s hard to get ventilators working right. Sometimes they push in too much air and injure your lungs. Sometimes they push in too little air and you suffocate. There are big fights about what settings to run ventilators on for which patients. For a while, doctors fought over whether to set ventilators on high vs. low, with many experts in each camp. Researchers formed a consortium called PETAL to study this.
Then, an institutional review board blocked the study:
> Its director, ethicist Jerry Menikoff, had decided maybe it was unethical to do RCTs on ventilator settings at all. He asked whether they might be able to give every patient the right setting while still doing the study. The study team tried to explain to him that they didn’t know which was the right setting, that was why they had to do the study. He wouldn’t budge.
Yes, putting someone on the wrong ventilator setting could kill them! That's obviously evil! Unfortunately, nobody knew which setting was the wrong one! The only way to find out was to try both, in a systematic and scientifically-valid fashion.
The FDA thinks similarly. In late 2021, they canceled trials of Paxlovid because it was immoral to have a control group. They did not then _waive the trial requirement_, meaning Paxlovid was both too proven to deny but too unproven to be administered.
I understand control groups in general, those are fine. But this is specifically in trials where people are pinning their last hopes out of desperation on some medicine and some random drop of the dice seals their fate.
I'd imagine that somebody who has, say, a 10% chance to die in 3 month, is also quite desperate.
(b) most therapies don't improve prognosis in terminal cases and some make it worse. We don't know which beforehand. In the cases where the therapy makes it worse, was it therefore immoral to not put more people in the control group?
I'd argue the lack of knowledge makes it a wash morally. If we knew beforehand whether the therapy would be effective, we wouldn't need the control group, but we also wouldn't need the study.
It is rather akin to saying that I can't tell whether seatbelts reduce car-crash fatalities simply by comparing collision fatalities from 1967 seatbelt-lacking car models with otherwise-identical 1968 seatbelt-equipped models; I would need to actually randomly and secretly sabotage a certain percentage of the seatbelts from 1968-model cars, while deliberately ignoring everything I know about prior fatality statistics.
In medicine, you get confounding factors like change in standard of care year-to-year and facility-to-facility. You almost never get the kind of "clean-room" trials you get in mechanical engineering (and, indeed, the processes to create them would often themselves be unethical). So the best you usually get is trying to reason around (to torture the analogy a bit) "Well we introduced seatbelts three years ago and relative to the year prior to that, fatalities went way down... Oh wait, but COVID also happened the same year we introduced seatbelts and everyone stopped driving" if you compare a current trial to past non-trial standard care as the control group.
What is the Bayesian prior on "After receiving the COVID vaccination, patient died when they were struck by lightning?"
This is what I mean when I say the 'clean room' practices that are standard for most other fields of science would be considered unethical for medical trials. You can't, generally, lock people in a box for months to eliminate other confounding factors when trialing medicine; the best approach we have, therefore, is to minimize confounding factors by minimizing variables in space, time, &c. Yes, if we could lab-rat humans, keep them in controlled environments perpetually, we could use the previous in-a-box state as a comparison to the current state, probably. That's obviously a non-starter.
(There are some categories of medical research where time-variance has been used; it's just not generally an acceptable signal source, IIUC, for drug and therapy trials. If for no other reason than not nearly enough information has been captured about unrelated past patients to be compared to a current trial because relevant information to monitor was not known when monitoring past patients).
Mathematically not difficult to deal with, which is why you intuitively know the answer already, because it's approximately the same way your brain works naturally. The chance of dying when you are struck by lightning is about 10%,[1] which completely overwhelms the chance of the vaccine coincidentally killing you at the same moment by several orders of magnitude; while you could use the this datapoint if you want, Bayesian analysis will still confirm that it has approximately zero evidence supporting (or refuting) that the vaccine causes death, so Bayes' theorem effectively drops that patient out of the analysis. Which is the same thing you'd probably have done intuitively, unless some kind of formal controlled-test study rule prevented you from doing what would normally be the correct procedure. (Or worse, forced you to subject an unvaccinated control-group patient to a lightning strike, just to maintain control...?)
But, since your patient died from the lightning strike rather than surviving it, there is a small signal present that points towards "the vaccine increased the chance of the lightning strike being fatal", which is a postulate that deserves a high initial skepticism until someone can propose a mechanism. But if you notice that multiple people die from lightning strikes after getting vaccinated, such that their lightning-strike survival rate is below the unvaccinated population's, you can start to update on that, and if it keeps happening, it becomes worth your time to investigate a potential mechanistic explanation. Like, the vaccination causing people to be less sweaty somehow.
[1] https://www.britannica.com/one-good-fact/what-are-the-odds-o...
Sweatiness is a good example of the sort of thing that would be hard to determine by comparing to past sample groups, since it's a rarely recorded piece of data.
This mathematical procedure is usually called "applied common sense", and if you are attempting to argue that it's impossible, you would in the process be proving that nobody can ever learn anything about anything.
That is a valid concern and is one of the three known serious adverse events (SAE) experienced during the Moderna covid-19 vaccine testing.
https://www.fda.gov/media/144434/download
> As of December 6, 2020, there were 3 SAEs reported in the vaccine group: a 65-year-old participant with community acquired pneumonia 25 days after vaccination, a 72-year-old participant with arrhythmia after being struck by lightning 28 days after vaccination, and an 87- year-old participant with worsening of chronic bradycardia 45 days after vaccination. On FDA review of the narratives, none of these SAEs are assessed as related. There were no cases of severe COVID-19 reported in the study.
(/s if needed)
If you're interested in learning more, I would recommend learning about Judea Pearl's do-calculus, specifically the backdoor criterion. Although it isn't the end-all of causal analysis, it is a very useful non-experimental approach that will help you develop an appreciation for the benefits of controlled experiments.
As far as seat belts go, that's actually been something discussed a bit in economics. The main concern is if adding seat belts changes how people drive (confounding the actual effects of seat belts). The solution was to measure the protective effect of seat belts on occupants of the passenger seat in collisions involving drunk drivers.
The causality is pretty clear and while you might not claim that it double the life expectancy it would IMHO be immoral not to fast track the approval of that drug.
Given a treatment with a large effect size like penicillin, a causal link will be very easy to establish even with a suboptimal control group.
This is false. Control groups, preferably in double-blind studies, are an essential part of best practices. However, the bar for what constitutes evidence is much lower than that.
Evidence is any fact that makes a relevant conclusion more or less likely. Evidence need not be conclusive in and of itself. Over time, the cumulative effects of less-strong evidence can form the basis for a reasonable inductive conclusion. Sorry to be trite, but as an example, a person can have evidence that their romantic partner loves them without the use of an identical twin.
Insisting on gold standard medical evidence before allowing someone to undergo life-saving treatment—when the preponderance of the evidence that does exist supports that treatment—is, to be blunt, the very definition of depraved heart murder. It demonstrates a wanton disregard toward human life in the face of the known likelihood that it will result in some number of deaths.
More broadly, however, it is an extremely poor policy, in that this meme both weakens society's critical thinking generally and—among those who see through the elitist charade—significantly weakens the respect of those scientists who make the claim.
I wouldn't go that far. I think that a paradigm built upon a broader evidence base -- e.g. with far more extensive postmarketing surveillance of drugs -- would be more ethical, of more benefit to society, and ultimately more effective.
Double-blinded studies can miss, can be confounded by placebo effects, can easily be confounded by crooked researchers, and are frequently just plain unethical from first principles. I don't think that they should be considered "essential."
RCTs are the gold standard for demonstrating efficacy precisely because of the controls. I agree that they're not going to give you enough info about potential side-effects - a thorough monitoring program is definitely necessary for that.
But without RCTs, showing that a drug works would be much harder. How would you weed out the snake oil?
> How would you weed out the snake oil?
The current paradigm is "better 10,000 people die of neglect than 1 person die of snake oil or quackery." I'm okay with a little bit of snake oil if it means that more drugs are being introduced more quickly, and I trust practitioners and patients to, more often than not, determine the therapeutic regimens that are right for them.
Compare that to establishing a bespoke chemical process for each drug, or messing with purification of natural biologicals, or fusing antibodies to protein or peptides to grow inside a whole cell.
They should be actually cheap. They aren't because new.
Humira is quite a bit harder to manufacture cleanly than a peptide or mRNA, and still harder than a plain solid state synthesized and folded protein. It requires a lot of post translational modification, which means cellular machinery, which means a whole bacterial cell you now have to grow, feed and remove from the product.
Agreed that there should be a faster way to trial drugs and get them to market. Though I've heard that the "slowness" of the FDA is actually overstated; not sure how true that claim is.
Any statistically significant difference there can then incentivize a drug research company to invest in the (expensive) clinical controlled trial process.
It's strange that people here are actually saying it's better to waste perfectly good research opportunities and watch patients die, than to risk having anything less than perfect evidence of efficacy.
They don't, though. They need a control group.