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. 2021 Apr 22;384(16):1572-1573.
doi: 10.1056/NEJMc2102446.

Platform Trials - Beware the Noncomparable Control Group

Lori E Dodd  1 , Boris Freidlin  2 , Edward L Korn  2
Affiliations

Platform Trials - Beware the Noncomparable Control Group

Lori E Dodd et al. N Engl J Med. .
No abstract available

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Figures

Figure 1
Figure 1. Hypothetical Example of How Nonconcurrent Randomization Could Bias the Results of a Trial.
Panel A shows the 30-day in-hospital mortality from Covid-19 in April 2020 (12.9% [SE, 0.3]), in May 2020 (5.9% [SE, 0.2]), and over both months (9.3 [SE, 0.2]) (data are from eFig. 2B in Asch et al.). Panel B shows the data from a hypothetical trial for an ineffective new agent used in May 2020 as compared with a control treatment used in April and May 2020. The data show that mortality was lower by 37% with the ineffective new agent than with the control treatment.
See this image and copyright information in PMC

References

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