When my dad was in the hospital after having bypass surgery, a lady came around doing aromatherapy. I know in my heart it's a bunch of crap, and I know 100% my dad would think so in better health, but in this beat down state he seemed to take some sort of solace in it so I didn't say a word.
All this is to say, sometimes you just need let people have their placebos, because it can be more cruel not to.
Not only that, but the placebo effect is one of the most reliably powerful effects in all of medicine. It's not just a form of solace, it is often a critical part of recovery. In many cases it is more important to receive an "effective" placebo than to receive actual medical intervention.
Perfumes have been used for thousands of years and shops are investing into the right aromas to make their customers buy more.
I wouldn’t be surprised if the right aromas can have a positive influence on a patients mood, compared to “the uplifting smell of a hospital ward”.
Like, basically all clinical trials with a placebo arm and a no treatment arm (particularly for pain and depression) show a pretty significant difference between the two arms, suggesting that something's going on there.
There was that famous meta-analysis from 2001 that showed no significant effects, but that averaged over a _lot_ of trials where we wouldn't expect much of an effect (cancer, particularly).
When you look at trials that could plausibly be placebo-susceptible you do find an effect.
Can you explain why you think it's mostly regression to the mean?
> There was that famous meta-analysis from 2001 that showed no significant effects, but that averaged over a _lot_ of trials where we wouldn't expect much of an effect (cancer, particularly).
This is the exact meta-analysis that I was referring to.
I'd need to go back to my PhD to remember all the flaws I found with that approach, and the vast number of studies (including meta-analyses) that found statistically significant placebo effects following this.
Particularly for pain, there's biochemical evidence of placebo effects being created due to sugar pills, and these effects being reversed by opioid antagonists (naloxone, particularly), so the evidence is particularly strong for this.
If I get a chance this week, I'll review my thesis for the citations that I knew back then (but it's been over 10 years since my viva and I no longer work in the area so can't recall off the top of my head).
(This is standard for Cochrane reviews, btw and definitely a good thing). I fundamentally disagree with the approach of this review and analysis (placebos are not a generic effect (apart from pain)) but love Cochrane in general).
All this is to say, sometimes you just need let people have their placebos, because it can be more cruel not to.