Quote, "A placebo arm is needed for comparison to study (test) criteria in question."??
That's actually not what a placebo arm is or for, or does, etc; not even close.
The "placebo effect" is used for many issues and to reveal many issues surrounding the testing and attempts to proving the EFFICACY (statistical relevance) of a drug/treatment process in medicine. It's used to screen for numerous issues that are very difficult to otherwise prove, screen or account for when trying to show efficacy and most important also, understand side-effects in human population sub sets. Since it's impossible (because of costs, time, logistics, etc) to test every new drug or medical or surgical procedure on literally millions of patients - one must use statistical methods of "sampling" and try and get good cross representations of all possible human sub set groups in good trial design (for example younger patients response versus older patients, patients with concomitant diseases or health issues versus those deemed 100% "healthy", aka are some patients taking other medications that may interact with the proposed new drug- placebo helps test and show any statistical relevant interactions if they exists, testing for side effect issues one of the most critical things a placebo arm reveals- as in did 30% of patients get eye pain post treatment regardless of whether it was the "cell" injection or a neutral "saline eye wash solution" or similar- that is what placebo does and is used for among many, many other things.)
Placebo testing is not limited by any means to orally ingested medications or "pills" - where is that written? Now days they even test some surgical and other medical procedures against "sham" or placebo arm treatments- as placebo has been shown to have not only "psychological" effects but neurological, physiological, pain and brain receptor effects, immune up or down regulation effects- pretty much anything and everything involving the human body. It's one of the greatest mysteries of all of medicine.
The single biggest area one can see OCAT needing "placebo testing" IMO would be for side effect statistical measuring and ability to show the FDA or similar with hard numbers the amount, or lack of amount. from a statistical human population standpoint- of what side-effects are known, expected and thus proven safe or not across all populations sub-sets (old, young, middle age, taking other drugs, having other medical conditions/health problems, etc) - the stuff the FDA always wants to know and will demand is in a drug "cut sheet" as quantified numbers so a practicing physician can know what to expect.
In other words, the physician will be able to read in the drug labeling and "cut sheet" that 18% of treated patients are likely to have "immediate eye swelling for the first week of post treatment" and 3% showed possible severe blah, blah and if blah, blah is seen- consider it a potential serious side effect and monitor the patient for X number of weeks. THAT is what a drug "cut sheet" looks like. Not the little one pager you get at the pharmacy like Wallgreens or whatever. If you've ever been handed a sample pack of a new drug by your physician- it will almost always have in it the true "cut sheet" - which is a huge, multi fold out piece of paper than when opened up typically takes two hands to hold, is double sided and printed in micro print- enough to fill pages and pages of a small book. It shows the atomic structure of the drug, describes the chemistry of it, the "theoretical mechanism of action" and massive amounts of info on trial results, statistics, expected side effects, etc. It's the equivalent of what will one day be published in the "Physicians Drug Reference" or a similar tome and the pharmacological text books and similar.
That is a "tiny" bit of info as to what "placebo" is about and used for- it's massively complex and way, way beyond the simplified, totally incorrect one-liner given in the other post. And it's not limited to oral medications or "pills" or whatever the claim was. Not by a long shot.
