2/n The paper is here. It is truly woeful, but worth reading just to see how easy it can be to make a plausible-sounding argument if you are very free with your methodologyhttps://www.mdpi.com/2076-393X/9/7/693/htm#B6-vaccines-09-00693 …
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3/n The authors did two things - they calculated a Number Needed To Vaccinate (NNTV) from a propensity-matched cohort study done in Israel. They also calculated the number of deaths reported through the Dutch vaccine reporting systempic.twitter.com/NLHZ2UYNmh
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4/n They then compared these two numbers, arguing that since the NNTV was almost equal to the number of deaths reported after vaccination in the Netherlands, vaccinations are not a good interventionpic.twitter.com/YYCJp7juep
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5/n The first obvious issue here is in the NNTV It is not a great statistic, but here it is used in a WILDLY misleading waypic.twitter.com/RD4Js8byZ0
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6/n NNTV is easily calculated - you just divide 1 by the absolute risk difference between the vaccinated and unvaccinated groups. In the Israeli study, the risk of death was 0.006% higher in unvaccinated people, therefore the NNTV was 1/0.00006 = 16,667pic.twitter.com/OVwkvDdVA0
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7/n But here's the thing - this trial was only 6 weeks long. Fewer than 3% of the total population got COVID-19 in that time, compared to at least 30% of the entire of Israel over the last 12 months
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8/n This means that the NNTV from this study is INHERENTLY MISLEADING unless you assume that vaccines will stop working entirely after the 6-week period (obviously false)
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9/n If you extrapolate this efficacy out linearly, and assume that the RELATIVE risk of death after vaccination remains similar over time, at 52 weeks you'd get an NNTV of 1/((0.00006/6)*52) = 1 per 1,960
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10/n If you assume that everyone who stays alive will get infected without a vaccine eventually - which is a fact - the ABSOLUTE risk difference approaches the RELATIVE risk difference, and so NNTV = 1/0.84 = 1.2 I.e. 1 life saved for every 1.2 vaccines given!
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Replying to @GidMK
This particular number 1.2 is impossible, isn't it? It seems to me that inherently this calculation assumes that everyone who gets infected will die - which obviously isn't true.
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Yes I corrected further down the thread - mixed up the deaths and cases in my calculation!
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