There’s this clinical trial where the study drug was tested with the following scheme: 1 substudy where the study drug was compared to a placebo comparator (both flat-dosed), & another substudy within the same trial where the study drug was also compared to a placebo comparator, but with a regimen where both arms were dose-escalated after 3mo, up to a given level.
As this scheme is not that common for me, my question is the following: how do you have to handle the type I error in this case? It depends on the question(s) you’ll tell me, but I just wanted to ask around, because it’s an interesting case.
Personally, I think the FWER has to be managed since the same question is asked (does the study drug differ from placebo), so I’d split the alpha, but I am not sure.
here is the link to the trial record in question
I know you can handle this multiple testing in other ways than the alpha spliting, so you can generalize my take on split the alpha or any other method to handle such case.
But there are also several sub-questions:
- is it a real case of multiple testing?
- the company decided to use this 2-parallel group with each substudy having its comparator arm (to keep the double-blinding for the number of tablets administered I presume), but was this mandatory? If not, what would have been the implications in terms of statistical comparison? Just a bias on the fact one arm would not have been blinded?
So perhaps the answer will be obvious for some, but I am not certain about how to view things.
I tried to have a look in the related topics on the forum but I saw nothing close, sorry if this is the case.