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. 2022 Sep 28;174:32–42. doi: 10.1016/j.zefq.2022.08.003

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Number of COVID-19 trial registrations over time. Cumulative registration (dark blue) and number of registrations per month (orange). Of note, 22 RCTs were registereg before January 1^st 2020, before the pandemic started but were then adapted to assess COVID-19 related interventions or to include COVID-19 patients.