biostudies-literatureUnknown46(1)Zeilinger EL<h4>Background</h4>The effectiveness of cloth face masks to prevent viral spread has not yet been conclusively established. In this meta-analysis, we evaluate their effectiveness in comparison to standard medical/surgical and N95-typed masks against viral spread.<h4>Methods</h4>We identified literature through a systematic search in three databases and meta-analytically synthesized relevant studies by means of random-effects as well as multilevel modelling.<h4>Results</h4>Twelve studies comprising k = 28 effect sizes (N = 338) were included. Medical/surgical and N95-typed masks outperformed cloth masks, yielding a large effect (g = 1.40). This effect remained robust when data were grouped according to comparisons with medical/surgical masks (g = 1.25) and N95-typed masks (g = 1.29). However, effects were differentiated according to mask fit, indicating reversals of signs when cloth mask effects were compared with ill-fitting medical/surgical and N95-typed masks (gs = -12.50 and - 10.90, respectively).<h4>Conclusions</h4>Cloth face masks were found to have significantly poorer filtering performance than medical/surgical masks and N95 masks, but only if non-cloth masks were properly fitted. Our results illustrate the necessity of using well-fitting medical/surgical or N95-typed masks to prevent viral spread, although some allowance should be made in circumstances where higher compliance with cloth mask mandates are expected.Journal of public health (Oxford, England)e84-e90https://www.ebi.ac.uk/biostudies/studies/S-EPMC10901268biostudies-literatureEffectiveness of cloth face masks to prevent viral spread: a meta-analysis.PMC10901268Oberleiter SBrunevskaya NPietschnig JWurzer JMasel EKFries JKum LHerscovici AZeilinger ELFuchs AfalseEffectiveness of cloth face masks to prevent viral spread: a meta-analysis.<h4>Background</h4>The effectiveness of cloth face masks to prevent viral spread has not yet been conclusively established. In this meta-analysis, we evaluate their effectiveness in comparison to standard medical/surgical and N95-typed masks against viral spread.<h4>Methods</h4>We identified literature through a systematic search in three databases and meta-analytically synthesized relevant studies by means of random-effects as well as multilevel modelling.<h4>Results</h4>Twelve studies comprising k = 28 effect sizes (N = 338) were included. Medical/surgical and N95-typed masks outperformed cloth masks, yielding a large effect (g = 1.40). This effect remained robust when data were grouped according to comparisons with medical/surgical masks (g = 1.25) and N95-typed masks (g = 1.29). However, effects were differentiated according to mask fit, indicating reversals of signs when cloth mask effects were compared with ill-fitting medical/surgical and N95-typed masks (gs = -12.50 and - 10.90, respectively).<h4>Conclusions</h4>Cloth face masks were found to have significantly poorer filtering performance than medical/surgical masks and N95 masks, but only if non-cloth masks were properly fitted. Our results illustrate the necessity of using well-fitting medical/surgical or N95-typed masks to prevent viral spread, although some allowance should be made in circumstances where higher compliance with cloth mask mandates are expected.2024-01-01T00:00:00Z2024 Feb2025-04-22T06:36:21.478Z2025-04-05T21:46:32.318ZS-EPMC109012683793496410.1093/pubmed/fdad205