6/28/23, 1:14 AM DANMASK-19 Pathway Feedback Search Clinical Topics Home Studies DANMASK 19 DANMASK 19 Disease COVID 19 infection Trial question What is the effect of adding a mask recommendation to other public health measures to prevent SARS-CoV-2 infection? Study design Multi-center Open label RCT Population Characteristics of study participants 52.0% female N = 6024 48.0% male 6024 patients (3116 female, 2908 male) Inclusion criteria: adults spending > 3 hours/day outside the home without occupational mask use Key exclusion criteria: previously tested positive for corona-virus, wearing facial mask for work Interventions N=2392 face mask (mask wearers) N=2470 control (non-mask wearers) Primary outcome Severe acute respiratory syndrome coronavirus 2 infection at 1 month 2.1 % 2.1 https://web.pathway.md/studies/reczXwjy7VXIH6wXY 1/2 6/28/23, 1:14 AM DANMASK-19 Pathway 1.8 1.6 % 1.1 % 0.5 % No significant difference 0.0 % Face mask Control No significant difference in SARS-CoV-2 infection at 1 month (1.8% vs. 2.1%; OR 0.82, 95% CI 0.54 to 1.23) Secondary outcomes No significant difference in PCR positivity for other respiratory viruses (0.5% vs. 0.6%; OR 0.84, 95% CI 0.35 to 2.04) No significant difference in positivity for any virus including SARS-CoV-2 infection (0.5% vs. 0.8%; OR 0.58, 95% CI 0.25 to 1.31) No significant difference in health care-diagnosed COVID-19 (0.2% vs. 0.4%; OR 0.52, 95% CI 0.18 to 1.53) Conclusion In adults spending > 3 hours/day outside the home without occupational mask use, face mask was not superior to control with respect to SARS-CoV-2 infection at 1 month. Reference Henning Bundgaard, Johan Skov Bundgaard, Daniel Emil Tadeusz Raaschou-Pedersen et al. Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers : A Randomized Controlled Trial. Ann Intern Med. 2020 Nov 18;M20-6817. Open reference URL https://web.pathway.md/studies/reczXwjy7VXIH6wXY 2/2