I am not a practitioner, so I have no idea if this is actually plausible, but it would seem absurd to me for an experimental, out-of-left-field treatment for Alzheimers, in a <10 person study, could be denied a control group on ethical grounds. There are tens if not hundreds of millions of Alzheimer's patients not receiving this potential treatment already.
This. There is basically zero chance that an ethics review would see this as a case in which a control group is unethical. I have been through plenty of IRB processes.
Resource constraints are a much more plausible explanation - running the study with a control group would cost twice as much (in time as well as money). This is either a pilot to apply for funding to run a better-controlled trial, or it's just not scientifically serious. Both are very plausible, in my experience.
Thanks for the perspective, I have only done data analysis after the data is generated, and never have actually had to deal with an IRB directly for the design of a study.
