Yet another open-label study posted on HN. The placebo effect will play a large part in every patient treated with this, so how do we know if the pill had any effect over and above placebo? Really, this study is a waste of time and money.
It's a first step. Preliminary studies like this are important: before investing a huge amount of money into proper studies, it's fiscally prudent to take smaller steps.
Instead of going straight for the generic criticism, you might ask "what's cool about this study?"
It doesn't really tell us anything, like all open-label studies (except perhaps whether or not the treatment is dangerous and whether it might provide a benefit). Also it doesn't really cost any more to do a small-scale placebo-controlled trial vs an open-label study.
Overall open-label studies just give false hope to people who don't understand science and the placebo effect (i.e. most people).
I've never seen (although it might be possible) the placebo effect cure a bacterial infection. C. difficle infections are notoriously difficult to treat, even with specific drugs like Dificid.
If an open-label, uncontrolled study of fecal transplants cures a ton of people, that's very strong evidence that it works.
Closed, double-blinded clinical trials offer different value for different diseases.
That's why the FDA will accept an open-label, uncontrolled clinical trial for a drug that treats cancer.
The study didn't show that the treatment cured the infection. It just found that bowel movements decreased, and patient self-rated health increased. The placebo effect has been shown to have a significant effect on diarrhea for IBS:
Also, there are currently no RCTs showing the effectiveness of fecal transplant for C difficile, and a Nature review cautions that there will be a strong placebo effect for invasive procedures:
I didn't look into the details of this particular trial, so if in fact it did just look at patient self-rated health then yes, placebo effect could be a big factor.
I have seen other open-label uncontrolled studies for fecal transplant that had some pretty spectacular outcomes. Is such a trial as rigorous as a RCT? No, but it's a pretty positive signal.
I didn't say I understood how the placebo effect works (although perhaps I have a better idea than many people, as I've written a book about it).
What I meant is that - as I pointed out above - this study will have a siginificant placebo effect, and the results should therefore be treated with extreme caution.
We still have no idea whether this treatment actually works, and I'm constantly surprised that studies like this continually make the first page of HN.
I think the problem is that most people don't know that the placebo effect actually exists (or at least, they forget about it when they read a study like this, or downplay its significance). Even many researchers underestimate the placebo effect, and then we end up spending billions of dollars a year on a useless treatment until someone actually proves that it is no better than placebo.
"this study will have a siginificant placebo effect, and the results should therefore be treated with extreme caution"
You have no way of proving this. Let's face it, we do not have a good grasp on the factors involved in the placebo effect, for example we don't know whether someone needs to be susceptible to it for it to work, we don't know how to reliably trigger it, we don't know whether there are limits on its effects in the body. As you're an author of a book on the subject, you already know all this.
Regarding people's hope, there's no guarantee that people will read more into the study than they should, but we should give people the benefit of the doubt. It's fairly common to read about promising scientific studies that take a long time to develop into something more tangible, if at all (for example, here's a whole website full of such stories... http://phys.org/). Anyone with an interest in science is going to be used to these stories by now, but it doesn't mean there isn't something promising that can come of single research studies, once the data can be verified.
The study just looked at number of bowel movements and self-rated health, both of which have been shown to have a significant placebo effect. See for example:
A Nature review looking at fecal transplants for C difficile cautions that a strong placebo effect is common with invasive procedures. (This particular study isn't invasive, but it is highly novel, and that has also been shown to correlate with a large placebo effect).
From your second link: "FMT holds considerable promise as a therapy for recurrent CDI but well-designed, RCTs and
long-term follow-up registries are still required. These are needed to identify the right patient, efficacy and safety profi le of FMT before this approach can be widely advocated."
I don't disagree with this conclusion at all. The existing data is very encouraging, but more studies are needed before it can be considered for widespread use.
Also, it's worrying that the author says that they elected not to do a placebo-controlled trial due to the "efficacy" of fecal transplant. However there are no RCTs for fecal transplant, and Nature cautions that there is likely to be a large placebo effect.
Perhaps the difference is that falling at terminal velocity isn't likely to be affected by the placebo effect, whereas diarrhea has been proven to be highly amenable to it (see my comments above).
Anyway, thanks for helping to prove my point that most people don't understand the placebo effect (the downvotes also help to prove it :)
I don't understand your point. Just as the survivability of a fall from great heights is unlikely to be affected by the placebo effect, I would expect that kicking an antibiotic-resistant infection that's had you hospitalized for weeks/months would be unlikely to be affected.
I don't see how diarrhea factors into it. Are you saying that you think the patients will experience less diarrhea because they knew they were swallowing poop?
As I pointed out above, if you actually look at the study itself (not the NY Times article), the participants didn't "kick an antibiotic resistant infection" as you put it. All they did was have reduced bowel movements and better self-rated health.
Interestingly the study did a stool test for C dificile before the study (to see if the participants actually had the infection) but they didn't do any stool analysis after the study.
All in all, there are a lot of deficiencies with this study and it doesn't really tell us much.
And yes, the placebo effect has been shown to reduce diarrhea (as I pointed out above). This is expected, as the HPA axis (the body's stress system) is one of the systems that controls bowel movement.
