Thread by @ncdave4life

@ScienceBlog3 @fischerfischy @Nockit1 @Michael_D_Crow @Michael11351713 @AndreGrossza @Anvndarnamn5 @Veritatem2021 @BenKoby1911 @Mark_A_Lunn @judgementalbe1 @AristotleMrs @ChrisBBacon3 @Coleski14 @Willard1951 @wallytoms0 @Climatehope2 @LesserMegadeath @JusticeTrudeau @WernerReinhard5 @S_D_Mannix @ammocrypta @JimBlack48 @glinch72 @Jaisans @DenisDaly @stitchnstab @CarrudoDon @LiveLifeBK24 @TheDisproof @priscian @Joeyd87745119 @Devonian1342 @Data79504085 @Hji45519156 @waxliberty @SuperFoxyLoxy @JaapTitulaer @wjack76995 @Rocky35418823 @NobaconEgbert @balls95652097 @JustThi30117912 @SniemN @BointonGiles @SeekerTheGreat1 @ubique60 @CDMarshall7 @EthonRaptor @RMcgillss 1/7」 Yes, the reason that the Phase 3 vaccine trials were about 20× that large is that in vaccine studies the medical ethics rules don't let them expose the study volunteers to the disease, so they have to wait for it to happen randomly.

@ScienceBlog3 @fischerfischy @Nockit1 @Michael_D_Crow @Michael11351713 @AndreGrossza @Anvndarnamn5 @Veritatem2021 @BenKoby1911 @Mark_A_Lunn @judgementalbe1 @AristotleMrs @ChrisBBacon3 @Coleski14 @Willard1951 @wallytoms0 @Climatehope2 @LesserMegadeath @JusticeTrudeau @WernerReinhard5 @S_D_Mannix @ammocrypta @JimBlack48 @glinch72 @Jaisans @DenisDaly @stitchnstab @CarrudoDon @LiveLifeBK24 @TheDisproof @priscian @Joeyd87745119 @Devonian1342 @Data79504085 @Hji45519156 @waxliberty @SuperFoxyLoxy @JaapTitulaer @wjack76995 @Rocky35418823 @NobaconEgbert @balls95652097 @JustThi30117912 @SniemN @BointonGiles @SeekerTheGreat1 @ubique60 @CDMarshall7 @EthonRaptor @RMcgillss 2/7」If they expect 5-10% of the study participants to be exposed, that means the study population must be 10× to 20× as large as would be needed to test therapeutics.

That's the answer to Q#1: because in a vax trial most of the enrollees aren't even exposed to the disease.

@ScienceBlog3 @fischerfischy @Nockit1 @Michael_D_Crow @Michael11351713 @AndreGrossza @Anvndarnamn5 @Veritatem2021 @BenKoby1911 @Mark_A_Lunn @judgementalbe1 @AristotleMrs @ChrisBBacon3 @Coleski14 @Willard1951 @wallytoms0 @Climatehope2 @LesserMegadeath @JusticeTrudeau @WernerReinhard5 @S_D_Mannix @ammocrypta @JimBlack48 @glinch72 @Jaisans @DenisDaly @stitchnstab @CarrudoDon @LiveLifeBK24 @TheDisproof @priscian @Joeyd87745119 @Devonian1342 @Data79504085 @Hji45519156 @waxliberty @SuperFoxyLoxy @JaapTitulaer @wjack76995 @Rocky35418823 @NobaconEgbert @balls95652097 @JustThi30117912 @SniemN @BointonGiles @SeekerTheGreat1 @ubique60 @CDMarshall7 @EthonRaptor @RMcgillss 3/7」And that leads to the Q#2: "Why did P3 vax trials tests for reduction of symptomatic disease, rather than mortality?"

@ScienceBlog3 @fischerfischy @Nockit1 @Michael_D_Crow @Michael11351713 @AndreGrossza @Anvndarnamn5 @Veritatem2021 @BenKoby1911 @Mark_A_Lunn @judgementalbe1 @AristotleMrs @ChrisBBacon3 @Coleski14 @Willard1951 @wallytoms0 @Climatehope2 @LesserMegadeath @JusticeTrudeau @WernerReinhard5 @S_D_Mannix @ammocrypta @JimBlack48 @glinch72 @Jaisans @DenisDaly @stitchnstab @CarrudoDon @LiveLifeBK24 @TheDisproof @priscian @Joeyd87745119 @Devonian1342 @Data79504085 @Hji45519156 @waxliberty @SuperFoxyLoxy @JaapTitulaer @wjack76995 @Rocky35418823 @NobaconEgbert @balls95652097 @JustThi30117912 @SniemN @BointonGiles @SeekerTheGreat1 @ubique60 @CDMarshall7 @EthonRaptor @RMcgillss 4/7」In a disease with, say 3% case fatality rate, you need 33× as many study participants to get large enough numbers of fatalities to get a statistically robust comparison between the different study cohorts, as you would need when just comparing symptomatic disease.

@ScienceBlog3 @fischerfischy @Nockit1 @Michael_D_Crow @Michael11351713 @AndreGrossza @Anvndarnamn5 @Veritatem2021 @BenKoby1911 @Mark_A_Lunn @judgementalbe1 @AristotleMrs @ChrisBBacon3 @Coleski14 @Willard1951 @wallytoms0 @Climatehope2 @LesserMegadeath @JusticeTrudeau @WernerReinhard5 @S_D_Mannix @ammocrypta @JimBlack48 @glinch72 @Jaisans @DenisDaly @stitchnstab @CarrudoDon @LiveLifeBK24 @TheDisproof @priscian @Joeyd87745119 @Devonian1342 @Data79504085 @Hji45519156 @waxliberty @SuperFoxyLoxy @JaapTitulaer @wjack76995 @Rocky35418823 @NobaconEgbert @balls95652097 @JustThi30117912 @SniemN @BointonGiles @SeekerTheGreat1 @ubique60 @CDMarshall7 @EthonRaptor @RMcgillss 5/7」If you need 30,000 study participants just to test for symptomatic disease, you'd need a million study participants to use mortality as an endpoint. That's just plain impossible.

@ScienceBlog3 @fischerfischy @Nockit1 @Michael_D_Crow @Michael11351713 @AndreGrossza @Anvndarnamn5 @Veritatem2021 @BenKoby1911 @Mark_A_Lunn @judgementalbe1 @AristotleMrs @ChrisBBacon3 @Coleski14 @Willard1951 @wallytoms0 @Climatehope2 @LesserMegadeath @JusticeTrudeau @WernerReinhard5 @S_D_Mannix @ammocrypta @JimBlack48 @glinch72 @Jaisans @DenisDaly @stitchnstab @CarrudoDon @LiveLifeBK24 @TheDisproof @priscian @Joeyd87745119 @Devonian1342 @Data79504085 @Hji45519156 @waxliberty @SuperFoxyLoxy @JaapTitulaer @wjack76995 @Rocky35418823 @NobaconEgbert @balls95652097 @JustThi30117912 @SniemN @BointonGiles @SeekerTheGreat1 @ubique60 @CDMarshall7 @EthonRaptor @RMcgillss 6/7」That's the answer to Q#2: The vax trials tested for symptomatic disease, rather than mortality, because testing for mortality would require a prohibitively large number of study participants.

@ScienceBlog3 @fischerfischy @Nockit1 @Michael_D_Crow @Michael11351713 @AndreGrossza @Anvndarnamn5 @Veritatem2021 @BenKoby1911 @Mark_A_Lunn @judgementalbe1 @AristotleMrs @ChrisBBacon3 @Coleski14 @Willard1951 @wallytoms0 @Climatehope2 @LesserMegadeath @JusticeTrudeau @WernerReinhard5 @S_D_Mannix @ammocrypta @JimBlack48 @glinch72 @Jaisans @DenisDaly @stitchnstab @CarrudoDon @LiveLifeBK24 @TheDisproof @priscian @Joeyd87745119 @Devonian1342 @Data79504085 @Hji45519156 @waxliberty @SuperFoxyLoxy @JaapTitulaer @wjack76995 @Rocky35418823 @NobaconEgbert @balls95652097 @JustThi30117912 @SniemN @BointonGiles @SeekerTheGreat1 @ubique60 7/7」And that leads to Q#3: "Why can trials of therapeutics (not vaxes) easily test for mortality endpoints?"

The answer is that when testing therapeutics, all the study participants are infected, rather than (eventually) 5-10%.

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