I wonder, are you allowed to sign people up to be part of a study within some parameters within some time period (e.g. "you're signing up to participate in a study in which we may lie to you sometime in the next year")?
Probably not. I've heard (from experimenters) that just getting economic experiments approved by a university institutional review board, where subjects are paid to sit in front of a computer and play a relatively simple game often with a chat feature to communicate with other subjects, can be problematic - and there's no deception going on in these.
The problem of published research findings not being reliable has been discussed here before.
One problem with RCTs that has received little attention is that, due to informed consent laws and ethical considerations, subjects are aware that they might be receiving sham therapy. This differs from the environment outside of the research setting, where people are confident that whatever their doctor prescribes is what they will get from their pharmacist. I can imagine many ways in which subjects' uncertainty about treatment assignment could affect outcomes (adherence is one possible mechanism). I wrote a short paper about this, focusing out what we would ideally estimate if we could lie to subjects, versus what we actually can estimate in RCTs (link). Here is the abstract:
Any thoughts on this? Is this a trivial technical issue or something worth addressing?