The DOI matches its Crossref record; 62 of the 62 references it cites were found in a registry or an index.
Effectiveness of N95 respirators versus surgical masks in protecting health care workers from acute respiratory infection: a systematic review and meta-analysis
Open accessAbstract
BACKGROUND: Conflicting recommendations exist related to which facial protection should be used by health care workers to prevent transmission of acute respiratory infections, including pandemic influenza. We performed a systematic review of both clinical and surrogate exposure data comparing N95 respirators and surgical masks for the prevention of transmissible acute respiratory infections. METHODS: We searched various electronic databases and the grey literature for relevant studies published from January 1990 to December 2014. Randomized controlled trials (RCTs), cohort studies and case-control studies that included data on health care workers wearing N95 respirators and surgical masks to prevent acute respiratory infections were included in the meta-analysis. Surrogate exposure studies comparing N95 respirators and surgical masks using manikins or adult volunteers under simulated conditions were summarized separately. Outcomes from clinical studies were laboratory-confirmed respiratory infection, influenza-like illness and workplace absenteeism. Outcomes from surrogate exposure studies were filter penetration, face-seal leakage and total inward leakage. RESULTS: We identified 6 clinical studies (3 RCTs, 1 cohort study and 2 case-control studies) and 23 surrogate exposure studies. In the meta-analysis of the clinical studies, we found no significant difference between N95 respirators and surgical masks in associated risk of (a) laboratory-confirmed respiratory infection (RCTs: odds ratio [OR] 0.89, 95% confidence interval [CI] 0.64-1.24; cohort study: OR 0.43, 95% CI 0.03-6.41; case-control studies: OR 0.91, 95% CI 0.25-3.36); (b) influenza-like illness (RCTs: OR 0.51, 95% CI 0.19-1.41); or (c) reported workplace absenteeism (RCT: OR 0.92, 95% CI 0.57-1.50). In the surrogate exposure studies, N95 respirators were associated with less filter penetration, less face-seal leakage and less total inward leakage under laboratory experimental conditions, compared with surgical masks. INTERPRETATION: Although N95 respirators appeared to have a protective advantage over surgical masks in laboratory settings, our meta-analysis showed that there were insufficient data to determine definitively whether N95 respirators are superior to surgical masks in protecting health care workers against transmissible acute respiratory infections in clinical settings.
Overview
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The cited source says what the claim attributes to it.
In the citing paper
“N95 FFRs have shown less filter penetration, fewer face seal leaks, and less total inward leakage than surgical masks under laboratory conditions (Lee et al., 2008;Grinshpun et al., 2009;Smith et al., 2016)”
From Size-selective Assessment of Respirator Protection against Airborne Fungi and (1→3)-β-D-glucan in Farms (2018) · cites this paper as Smith et al., 2016
The cited source says what the claim attributes to it.
In the citing paper
“In a meta‐analysis comparing surgical masks with N95 respirators, Smith 2016 pooled three trials and found an estimate of effect suggesting no difference for laboratory‐confirmed respiratory infections (OR 0.89, 95% CI 0.64 to 1.24) or ILI (OR 0.51, 95% CI 0.19 to 1.41) (Loeb 2009; MacIntyre 2011; MacIntyre 2013).”
From Physical interventions to interrupt or reduce the spread of respiratory viruses (2023) · cites this paper as Smith 2016
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Citations
Cites
Measuring inconsistency in meta-analyses
Higgins, J. P. T., Thompson, S. G., Deeks, J. J., & Altman, D. G. (2003) · BMJ · doi:10.1136/bmj.327.7414.557 · Cited by 63,139
Quantifying heterogeneity in a meta‐analysis
Higgins, J. P. T., & Thompson, S. G. (2002) · Statistics in Medicine · doi:10.1002/sim.1186 · Cited by 36,763
The Cochrane Collaboration's tool for assessing risk of bias in randomised trials
Higgins, J. P. T., Altman, D. G., Gotzsche, P. C., Juni, P., Moher, D., Oxman, A. D., Savovic, J., Schulz, K. F., Weeks, L., Sterne, J. A. C., et al. (2011) · BMJ · doi:10.1136/bmj.d5928 · Cited by 33,817
Dermyshi, E., Wang, Y., Yan, C., Hong, W., Qiu, G., Gong, X., & Zhang, T. (2017) · Neonatology · doi:10.1159/000454668 · Cited by 24,586
(2014) · Medical Entomology and Zoology · Cited by 17,633
Grading quality of evidence and strength of recommendations
(2004) · BMJ · doi:10.1136/bmj.328.7454.1490 · Cited by 8,477
Siegel, J. D., Rhinehart, E., Jackson, M. M., & Chiarello, L. A. (2007) · American Journal of Infection Control · doi:10.1016/j.ajic.2007.10.007 · Cited by 3,506
What to add to nothing? Use and avoidance of continuity corrections in meta‐analysis of sparse data
J. Sweeting, M., J. Sutton, A., & C. Lambert, P. (2004) · Statistics in Medicine · doi:10.1002/sim.1761 · Cited by 1,734
Kroger, A. T., ATKINSON, W. L., Marcuse, E. K., & Pickering, L. K. (1994) · PsycEXTRA Dataset · doi:10.1037/e546992006-001 · Cited by 1,712
Seto, W., Tsang, D., Yung, R., Ching, T., Ng, T., Ho, M., Ho, L., & Peiris, J. (2003) · The Lancet · doi:10.1016/s0140-6736(03)13168-6 · Cited by 863
Physical interventions to interrupt or reduce the spread of respiratory viruses
Jefferson, T., Del Mar, C. B., Dooley, L., Ferroni, E., Al-Ansary, L. A., Bawazeer, G. A., van Driel, M. L., Nair, N. S., Jones, M. A., Thorning, S., et al. (2011) · Cochrane Database of Systematic Reviews · doi:10.1002/14651858.cd006207.pub4 · Cited by 805
Review of Aerosol Transmission of Influenza A virus
Tellier, R. (2006) · Emerging Infectious Diseases · doi:10.3201/eid1211.060426 · Cited by 803
Transmission of influenza A in human beings
Brankston, G., Gitterman, L., Hirji, Z., Lemieux, C., & Gardam, M. A. (2007) · The Lancet Infectious Diseases · doi:10.1016/s1473-3099(07)70029-4 · Cited by 743
Milton, D. K., Fabian, M. P., Cowling, B. J., Grantham, M. L., & McDevitt, J. J. (2013) · PLoS Pathogens · doi:10.1371/journal.ppat.1003205 · Cited by 669
Droplet fate in indoor environments, or can we prevent the spread of infection?
Morawska, L. (2006) · Indoor Air · doi:10.1111/j.1600-0668.2006.00432.x · Cited by 646
What Is an Intracluster Correlation Coefficient? Crucial Concepts for Primary Care Researchers
Killip, S. (2004) · The Annals of Family Medicine · doi:10.1370/afm.141 · Cited by 622
(1994) · PsycEXTRA Dataset · doi:10.1037/e546872006-001 · Cited by 490
Loeb, M., Dafoe, N., Mahony, J., John, M., Sarabia, A., Glavin, V., Webby, R., Smieja, M., Earn, D. J. D., Chong, S., et al. (2009) · JAMA · doi:10.1001/jama.2009.1466 · Cited by 465
Bałazy, A., Toivola, M., Adhikari, A., Sivasubramani, S. K., Reponen, T., & Grinshpun, S. A. (2006) · American Journal of Infection Control · doi:10.1016/j.ajic.2005.08.018 · Cited by 376
Grinshpun, S. A., Haruta, H., Eninger, R. M., Reponen, T., McKay, R. T., & Lee, S.-A. (2009) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459620903120086 · Cited by 353
SARS among Critical Care Nurses, Toronto
Loeb, M., McGeer, A., Henry, B., Ofner, M., Rose, D., Hlywka, T., Levie, J., McQueen, J., Smith, S., Moss, L., et al. (2004) · Emerging Infectious Diseases · doi:10.3201/eid1002.030838 · Cited by 345
Airborne Transmission of Communicable Infection — The Elusive Pathway
Roy, C. J., & Milton, D. K. (2004) · New England Journal of Medicine · doi:10.1056/nejmp048051 · Cited by 344
Performance of N95 Respirators: Filtration Efficiency for Airborne Microbial and Inert Particles
Qian, Y., Willeke, K., Grinshpun, S. A., Donnelly, J., & Coffey, C. C. (1998) · American Industrial Hygiene Association Journal · doi:10.1080/15428119891010389 · Cited by 298
Rebmann, T., Carrico, R., & Wang, J. (2013) · American Journal of Infection Control · doi:10.1016/j.ajic.2013.02.017 · Cited by 270
MacIntyre, C. R., Wang, Q., Cauchemez, S., Seale, H., Dwyer, D. E., Yang, P., Shi, W., Gao, Z., Pang, X., Zhang, Y., et al. (2011) · Influenza and Other Respiratory Viruses · doi:10.1111/j.1750-2659.2011.00198.x · Cited by 257
Lee, S.-A., Grinshpun, S. A., & Reponen, T. (2008) · The Annals of Occupational Hygiene · doi:10.1093/annhyg/men005 · Cited by 235
Using a Mathematical Model to Evaluate the Efficacy of TB Control Measures
Gammaitoni, L., & Nucci, M. C. (1997) · Emerging infectious diseases · doi:10.3201/eid0303.970310 · Cited by 227
Physical interventions to interrupt or reduce the spread of respiratory viruses
Jefferson, T., Mar, C. D., Dooley, L., Ferroni, E., Al‐Ansary, L. A., Bawazeer, G. A., van Driel, M., Nair, S. N., Foxlee, R., & Rivetti, A. (2010) · Cochrane Database of Systematic Reviews · doi:10.1002/14651858.cd006207.pub3 · Cited by 217
A randomized clinical trial of three options for N95 respirators and medical masks in health workers
MacIntyre, C. R., Wang, Q., Seale, H., Yang, P., Shi, W., Gao, Z., Rahman, B., Zhang, Y., Wang, X., Newall, A. T., et al. (2013) · American Journal of Respiratory and Critical Care Medicine · doi:10.1164/rccm.201207-1164oc · Cited by 189
Noti, J. D., Lindsley, W. G., Blachère, F. M., Cao, G., Kashon, M. L., Thewlis, R. E., McMillen, C. M., King, W. P., Szalajda, J. V., & Beezhold, D. H. (2012) · Clinical Infectious Diseases · doi:10.1093/cid/cis237 · Cited by 174
In vivo protective performance of N95 respirator and surgical facemask
Li, Y., Wong, T., Chung, J., Guo, Y. P., Hu, J. Y., Guan, Y. T., Yao, L., Song, Q. W., & Newton, E. (2006) · American Journal of Industrial Medicine · doi:10.1002/ajim.20395 · Cited by 159
Comparison of Performance of Three Different Types of Respiratory Protection Devices
Lawrence, R. B., Duling, M. G., Calvert, C. A., & Coffey, C. C. (2006) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459620600829211 · Cited by 127
The Spread of Influenza and Other Respiratory Viruses: Complexities and Conjectures
Hall, C. B. (2007) · Clinical Infectious Diseases · doi:10.1086/519433 · Cited by 113
Dispersion and Exposure to a Cough-Generated Aerosol in a Simulated Medical Examination Room
Lindsley, W. G., King, W. P., Thewlis, R. E., Reynolds, J. S., Panday, K. V., Cao, G., & Szalajda, J. V. (2012) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459624.2012.725986 · Cited by 96
MacIntyre, C. R., Wang, Q., Rahman, B., Seale, H., Ridda, I., Gao, Z., Yang, P., Shi, W., Pang, X., Zhang, Y., et al. (2014) · Preventive Medicine · doi:10.1016/j.ypmed.2014.01.015 · Cited by 90
Bischoff, W. E., Reid, T., Russell, G. B., & Peters, T. R. (2011) · Journal of Infectious Diseases · doi:10.1093/infdis/jir238 · Cited by 89
Chughtai, A. A., Seale, H., & MacIntyre, C. R. (2013) · BMC Research Notes · doi:10.1186/1756-0500-6-216 · Cited by 88
He, X., Reponen, T., McKay, R. T., & Grinshpun, S. A. (2013) · Aerosol Science and Technology · doi:10.1080/02786826.2013.829209 · Cited by 64
Rengasamy, S., Eimer, B. C., & Szalajda, J. (2014) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459624.2013.866715 · Cited by 61
Efficacy of three face masks in preventing inhalation of airborne contaminants in dental practice
Checchi, L., Montevecchi, M., Moreschi, A., Graziosi, F., Taddei, P., & Violante, F. S. (2005) · The Journal of the American Dental Association · doi:10.14219/jada.archive.2005.0288 · Cited by 61
Simulated workplace protection factors for half-facepiece respiratory protective devices
Duling, M. G., Lawrence, R. B., Slaven, J. E., & Coffey, C. C. (2007) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459620701346925 · Cited by 52
Transmission of influenza A in human beings
Tellier, R. (2007) · The Lancet Infectious Diseases · doi:10.1016/s1473-3099(07)70269-4 · Cited by 49
Quantifying exposure risk: Surgical masks and respirators
Diaz, K. T., & Smaldone, G. C. (2010) · American Journal of Infection Control · doi:10.1016/j.ajic.2010.06.002 · Cited by 49
Stockman, J. A. (2011) · Yearbook of Pediatrics · doi:10.1016/s0084-3954(10)79707-4 · Cited by 46
Debate on MERS-CoV respiratory precautions: surgical mask or N95 respirators?
Chung, S. J., Ling, M., Seto, W., Ang, B. S. P., & Tambyah, P. A. (2014) · Singapore Medical Journal · doi:10.11622/smedj.2014076 · Cited by 43
Tang, J. W.-T., Gao, C. X., Cowling, B. J., Koh, G. C., Chu, D. K. W., Heilbronn, C., Lloyd, B. K., Pantelic, J., Nicolle, A. D., Klettner, C. A., et al. (2014) · PLoS ONE · doi:10.1371/journal.pone.0107338 · Cited by 40
Protecting staff against airborne viral particles: in vivo efficiency of laser masks
Derrick, J. L., Li, P. T. Y., Tang, S. P. Y., & Gomersall, C. D. (2006) · Journal of Hospital Infection · doi:10.1016/j.jhin.2006.06.021 · Cited by 36
Wen, Z., Yu, L., Yang, W., Hu, L., Li, N., Wang, J., Li, J., Lu, J., Dong, X., Yin, Z., et al. (2012) · Aerobiologia · doi:10.1007/s10453-012-9286-7 · Cited by 32
Zhang, Y., Seale, H., Yang, P., MacIntyre, C. R., Blackwell, B. R., Tang, S., & Wang, Q. (2012) · Influenza and Other Respiratory Viruses · doi:10.1111/irv.12025 · Cited by 31
Zou, Z., & Yao, M. (2014) · Journal of Aerosol Science · doi:10.1016/j.jaerosci.2014.10.003 · Cited by 31
He, X., Reponen, T. A., McKay, R. T., & Grinshpun, S. A. (2013) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459624.2013.848037 · Cited by 29
Gawn, J. M., Clayton, M. P., Makison-Booth, C., & Crook, B. (2008) · Europe PMC (PubMed Central) · Cited by 27
Davidson, C. S., Green, C. F., Gibbs, S. G., Schmid, K. K., Panlilio, A. L., Jensen, P. A., & Scarpino, P. V. (2013) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459624.2013.818243 · Cited by 23
Respiratory Source Control Versus Receiver Protection: Impact of Facemask Fit
Mansour, M. M., & Smaldone, G. C. (2013) · Journal of Aerosol Medicine and Pulmonary Drug Delivery · doi:10.1089/jamp.2012.0998 · Cited by 22
Particulate masks and non‐powdered gloves reduce latex allergen inhaled by healthcare workers
Mitakakis, T. Z., Tovey, E. R., Yates, D. H., Toelle, B. G., Johnson, A., Sutherland, M., O’Hehir, R. E., & Marks, G. B. (2002) · Clinical & Experimental Allergy · doi:10.1046/j.1365-2745.2002.01432.x · Cited by 22
Roizen, M. F. (2007) · Yearbook of Anesthesiology and Pain Management · doi:10.1016/s1073-5437(08)70239-0 · Cited by 14
Surgical Masks vs N95 Respirators for Preventing Influenza
Bitar, R. A. (2010) · JAMA · doi:10.1001/jama.2010.193 · Cited by 14
Rengasamy, S., & Eimer, B. C. (2013) · Journal of Occupational and Environmental Hygiene · doi:10.1080/15459624.2013.818224 · Cited by 8
Surgical Masks vs N95 Respirators for Preventing Influenza
Clynes, N. D. (2010) · JAMA · doi:10.1001/jama.2010.194 · Cited by 8
Davidson, C. S., Green, C. F., Panlilio, A. L., Jensen, P. A., Stover, B. H., Roselle, G. A., Gibbs, S. G., & Scarpino, P. V. (2010) · Indoor and Built Environment · doi:10.1177/1420326x10378805 · Cited by 7
Indoor Air Quality: Recommendations Relevant to Aircraft Passenger Cabins
Hocking, M. B. (1998) · American Industrial Hygiene Association Journal · doi:10.1202/0002-8894(1998)059 · Cited by 6
Flagged first, then by citations
Research works printed but not linked: 1
- Higgins JPT, Green S, editors. Cochrane handbook for systematic reviews of interventions, version 5.1.0. Oxford (UK): Cochrane Collaboration; 2011. Available: handbook.cochrane.org/ (accessed 2014 Jan. 26).
Cited by
Sorted by citations
Alhazzani, W., Møller, M. H., Arabi, Y. M., Loeb, M., Gong, M. N., Fan, E., Oczkowski, S., Levy, M. M., Derde, L., Dzierba, A., et al. (2020) · Intensive Care Medicine · doi:10.1007/s00134-020-06022-5 · Cited by 2,105
Alhazzani, W. A., Møller, M. H., Arabi, Y. M., Loeb, M. B., Gong, M. N., Fan, E., Oczkowski, S. J. W., Levy, M. M., Derde, L. P. G., Dzierba, A. L., et al. (2020) · Critical Care Medicine · doi:10.1097/ccm.0000000000004363 · Cited by 1,578
Talic, S., Shah, S., Wild, H., Gašević, D., Maharaj, A. D., Ademi, Z., Li, X., Xu, W., Mesa‐Eguiagaray, I., Rostron, J., et al. (2021) · BMJ · doi:10.1136/bmj-2021-068302 · Cited by 850
Particle Sizes of Infectious Aerosols: Implications for Infection Control
Fennelly, K. P. (2020) · The Lancet Respiratory Medicine · doi:10.1016/s2213-2600(20)30323-4 · Cited by 621
Liang, M., Gao, L., Cheng, C., Zhou, Q., Uy, J. P., Heiner, K., & Sun, C. (2020) · Travel Medicine and Infectious Disease · doi:10.1016/j.tmaid.2020.101751 · Cited by 495
Metadata
- Authors
- Smith, J. D., MacDougall, C. C., Johnstone, J., Copes, R. A., Schwartz, B., & Garber, G. E.
- Affiliations
- University of Ottawa (CA)
- Venue
- Canadian Medical Association Journal
- Publisher
- CMA Impact Inc.
- Published
- 2016-03-07
- Volume
- 188
- Issue
- 8
- Pages
- 567-574
- ISSN
- 0820-3946 (ISSN-L)
- 1488-2329
- PMC
- PMC4868605
- OpenAlex
- W2293429114
- Cited by
- 328
- References
- 61
- Citations by year
- 2026: 3 · 2025: 5 · 2024: 15 · 2023: 28 · 2022: 31 · 2021: 74 · 2020: 150 · 2019: 13 · 2018: 4 · 2017: 4 · 2016: 1
- FWCI
- 1.27
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- Canadian Medical Association Journal (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Infection Control and Ventilation
- Health Sciences › Medicine › Infectious Diseases › Infection Control in Healthcare
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Occupational Health and Safety in Workplaces
- Keywords
- N95 respirators, surgical masks, healthcare workers, acute respiratory infections, pandemic influenza, respiratory protection, face masks, influenza-like illness, absenteeism, filter penetration, infection control
- MeSH terms
- Cross Infection, Humans, Masks, Occupational Diseases, Respiratory Protective Devices, Respiratory Tract Infections, Occupational Exposure
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review