A novel mask to prevent aerosolized droplet dispersion in endoscopic procedures during the coronavirus disease pandemic.

These were paired data; therefore, each person underwent 2 measurements: “with mask” and “without mask.” We then evaluated whether the differences between “with mask” and “without mask” values were normally distributed, using the Shapiro--Wilk test; as highly significant ( P = .005) results were observed, the assumption of normality was not met.

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