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“Is it never allowed to pull a control group from a different place? Doing so does not automatically disqualify the analysis but such an analysis does not enjoy the exalted gold-standard status of a randomized controlled trial.”

They are comparing two age groups. There is no way that this study would ever “enjoy the exalted gold-standard status of a randomized controlled trial.” No matter where the control data came from.

If they compared antibody levels before and after the vaccination, then the timing of the vaccination is irrelevant (we’re not looking at how many people got infected, which is dependent on outside factors). So the 16-25 group having been vaccinated earlier is a minor detail. I agree it should have been mentioned, and I wonder why they didn’t. But it’s not this big thing you make it out to be IMO.


Cris: Thanks for the comment. We agree that it is odd that they didn't simply acknowledge it. I flag this as a science communications issue.

A Palaz

Hi Kaiser,

So just some comments also on communication in this study.

The criteria for covid in study and the testing method and method diagnosis, I think may have some variation from protocol. Maybe also not, but it is not clearor separated.

The 12-15 yr old is likely supervised by guardian. So is some in 16-25 but its not clear.

The testing environment with screen tests at maybe some schools and maybe some college and university is I think not mentioned.

A possible in overlapping between reactoginicity set and efficacy set is not clear.

PS in note on your post on immunity a good interesting general site is


If I find the specific papers will link

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