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On July 10, 2020, Gilead announced

remdesivir treatment was associated with significantly improved clinical recovery and a 62 percent reduction in the risk of mortality compared to standard of care.... The mortality rate for patients treated with remdesivir in the analysis was 7.6 percent at Day 14 compared with 12.5 percent among patients not taking remdesivir (adjusted odds ratio 0.38, 95% confidence interval 0.22-0.68, p=0.001).

How is the 62% reduction calculated? Naively, a drop from 12.5% to 7.6% appears to be a 39% (=(12.5-7.6)/12.5) reduction.

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    12.5 x .62 = 7.75 – Carey Gregory Jul 11 '20 at 15:23
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    @CareyGregory: But would that mean if there was a slight drop in mortality from 12% to 11%, Gilead would claim a 92% drop in mortality!? – unutbu Jul 11 '20 at 15:43
  • Heh, good point. – Carey Gregory Jul 11 '20 at 15:44
  • And this is why, as a statistician, I wish we could all spend some time learning odds ratios and use those. It's not easy and they aren't intuitive, but once you get it you get it, and both positive and negative effects make sense. Percent changes are incredibly easy to misinterpret or misstate. – Bryan Krause Jul 11 '20 at 16:40
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    @Don_S It's better to just read the study numbers, which are not under dispute. "The mortality rate for patients treated with remdesivir in the analysis was 7.6 percent at Day 14 compared with 12.5 percent among patients not taking remdesivir (adjusted odds ratio 0.38, 95% confidence interval 0.22-0.68, p=0.001)" Stop there, ignore the rest. – Bryan Krause Jul 20 '20 at 1:53

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