6/28/23, 11:19 PM Medical masks in COVID-19 Pathway Feedback Search Clinical Topics Home Studies Medical masks in COVID 19 Medical masks in COVID 19 Disease COVID 19 infection Trial question Is medical mask noninferior to N95 respirator for COVID-19 prevention in healthcare workers? Study design Multi-center Open label RCT Population Characteristics of study participants 70.0% female N = 1004 30.0% male 1004 patients (699 female, 305 male) Inclusion criteria: healthcare workers who provided direct care to patients with suspected or confirmed COVID-19 Key exclusion criteria: nurses with 1 comorbidities; nurses who cannot pass an N95 respirator fit-test Interventions N=497 medical mask (medical mask worn when providing care to patient with febrile respiratory illness) N=507 N95 respirator (N95 respirator worn when providing care to patient with febrile respiratory illness) https://web.pathway.md/studies/reckdb65DCOKyVoYF 1/2 6/28/23, 11:19 PM Medical masks in COVID-19 Pathway Primary outcome Reverse transcriptase-polymerase chain reaction-confirmed COVID-19 10.5 % 10.46 9.27 7.8 % 5.2 % Difference not exceeding nonferiority margin 2.6 % 0.0 % Medical mask N95 respirator Difference not exceeding nonferiority margin in reverse transcriptase-PCR-confirmed COVID-19 (10.46% vs. 9.27%; HR 1.14, 95% CI 0.77 to 1.69) Secondary outcomes No significant difference in acute respiratory illness (5.4% vs. 6.1%; HR 0.89, 95% CI 0.53 to 1.49) No significant difference in lower respiratory infection or pneumonia (0.6% vs. 0.6%; HR 1.02, 95% CI 0.21 to 5.04) No significant difference in laboratory-confirmed infection (14.5% vs. 13.6%; HR 1.08, 95% CI 0.75 to 1.55) Safety outcomes No significant difference in adverse events. Conclusion In healthcare workers who provided direct care to patients with suspected or confirmed COVID-19, medical mask was noninferior to N95 respirator with respect to reverse transcriptase-PCR- confirmed COVID-19. Reference Mark Loeb, Amy Bartholomew, Madiha Hashmi et al. Medical Masks Versus N95 Respirators for Preventing COVID-19 Among Health Care Workers. Ann Intern Med. 2022 Dec;175(12):1629-1638. Open reference URL https://web.pathway.md/studies/reckdb65DCOKyVoYF 2/2