> So you're suggesting people with 1st dose keeping increasing the protection despite no booster in the delayed dose scenario. Possible, but important to point out that's not supported by the original RCT which takes no position on the matter.
No?
I'm suggesting we compare e.g. cases from day 21 to 42, when A) second dose is given on day 21, and B) second dose is given on day 42. (And people are blinded).
If efficacy B is at least half of efficacy A, then it makes sense to follow plan B.
Sorry I misunderstood. Your original phrasing implied a case when the protection increases (If month 1 / month 2 = 0.5 then month 2 is twice month 1).
Anyhow, it's important to note that the original RCT takes no position on what the result [month 1 / month 2] would be. It's a worthy thing to check, but it's not supported by the RCTs or CCTs.
>But one would expect that protection from days 21-41 without a second dose is comparable to protection from days 14-21.
I'm not sure that's enough for two reasons.
First, There's a study I linked to earlier, suggesting the 1st dose antibodies aren't good against the variants[0]. That would mean we need the booster ASAP.
Second, if the original efficiency is low, we're putting people at risk longer even if it stays about the same in 21-41. Imagine the 33% figure is correct. I don't think FDA would have approved the vaccine if efficiency < 50%, so should we keep people with such a low protection for another 20 days?
> First, There's a study I linked to earlier, suggesting the 1st dose antibodies aren't good against the variants.
It suggested the neutralization titers were worse, not that they were ineffective.
> so should we keep people with such a low protection for another 20 days?
We compare the ratio between people delayed and not delayed.
If a delayed person keeps, say, 50% efficacy, and the person with the second dose has 95% efficacy, giving two people 50% efficacy is better than giving one person 95% efficacy. That's why I suggested the specific figure of merit that I did.
(That is, imagine you produce 1 dose per 21 days, and there's two people in the world. You could give, in successive 21 day periods:
A 50% protection, B 50% protection, A 95% protection, B 95% protection.... (population efficacy 25%, 50%, 72.5%, 95%)
or you could give A 50% protection, A 95% protection, B 50% protection, C 95% protection). (population efficacy 25%, 47.5%, 72.5%, 95%).
>If a delayed person keeps, say, 50% efficacy, and the person with the second dose has 95% efficacy, giving two people 50% efficacy is better than giving one person 95% efficacy.
That logic breaks down when the divided efficacy is too low, even if it's formally half of the original. Say efficiency is 33% (and lets pretend the original is 66%). The people who got the 33% efficient vaccine go out and party, balancing out the effect. People think the vaccine doesn't help. Eventually nobody trusts your vaccine, and nobody shows up to get the second dose. I'm not sure 50% is high enough. Maybe it is, but just barely.
> See figure B here taken from the study. That's a large difference to my completely untrained eye.
So, LoQ means limit of quantification, aka the threshold below which things can't be measured in their assay technique. I know it's a log scale, but...
The study was barely able to detect the response to the baseline variant, so it doesn't take all that much of a drop to escape the study's quantification limit.
It's extremely misleading to plot the line all the way down to the bottom of the graph, when all you know is that it is (probably) less than the LoQ line. I say "probably" because this assumes the authors have accurately determined the LoQ, which is easy to mess up.
> That logic breaks down when the divided efficacy is too low, even if it's formally half of the original. Say efficiency is 33% (and lets pretend the original is 66%). The people who got the 33% efficient vaccine go out and party, balancing out the effect. People think the vaccine doesn't help. Eventually nobody trusts your vaccine, and nobody shows up to get the second dose. I'm not sure even 50% is high enough
Err.. Just to be clear, I never meant to suggesty ou'd take the ratio between month 1 and month 2. I tried to use parens to indicate the parameter that would be compared between the two groups (delayed and not delayed). Anything else wouldn't be an RCT, but just gawking at time series data...
No?
I'm suggesting we compare e.g. cases from day 21 to 42, when A) second dose is given on day 21, and B) second dose is given on day 42. (And people are blinded).
If efficacy B is at least half of efficacy A, then it makes sense to follow plan B.