Re-analysis on the statistical sampling biases of a mask promotion trial in Bangladesh: a statistical replication
Maria Chikina1, Wesley Pegden2, Benjamin Recht3
1Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA.
Trials
|September 15, 2022
Abstract:
A recent randomized trial evaluated the impact of mask promotion on COVID-19-related outcomes. We find that staff behavior in both unblinded and supposedly blinded steps caused large and statistically significant imbalances in population sizes. These denominator differences constitute the rate differences observed in the trial, complicating inferences of causality.
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