Cochrane · systematic review · CD006207

Physical interventions to interrupt or reduce the spread of respiratory viruses

Jefferson, T, Dooley, L, Ferroni, E, et al. · Cochrane Database of Systematic Reviews · 2023 · Cochrane Library

Acute Respiratory Infections2 versionsAMSTAR 2: not assessed
SoF tableOnly the outcomes this review put in its Summary of Findings table are listed (the Cochrane Handbook caps them at about seven per comparison). Its other analyses are not shown here.
Questions
12
current version
GRADE rated
12
No studies
0
Included studies
NR
No studies 0 · 0%Ungraded 0 · 0%Very low 4 · 33.3%Low 4 · 33.3%Moderate 4 · 33.3%High 0 · 0%

Ungraded means an effect was reported without a GRADE rating; it is not a gap. No studies means the review found nothing to answer the question. The six categories are a display order, not a score.

Questions and results

Show all 2 versions

Medical/surgical masks compared to no masks for preventing the spread of viral respiratory illness

Population: general population
3 questions
OutcomeEffectEvidenceStatus / GRADE
Viral respiratory illness ‐ influenza/COVID‐like illness
Medical/surgical masks vs no masks
RR 0.95 [0.84, 1.09]9 studies · 276917 participantsModerate
Downgraded: risk of bias
Viral respiratory illness ‐ laboratory‐confirmed influenza/SARS‐CoV‐2
Medical/surgical masks vs no masks
RR 1.01 [0.72, 1.42]6 studies · 13919 participantsModerate
Downgraded: imprecision
Adverse events
Medical/surgical masks vs no masks
no estimate extracted3 studies · 3 participantsVery low
Downgraded: risk of bias, imprecision

N95 respirators compared to medical/surgical masks for preventing the spread of viral respiratory illness

Population: general population and healthcare workers
4 questions
OutcomeEffectEvidenceStatus / GRADE
Viral respiratory illness ‐ clinical respiratory illness
N95 respirators vs medical/surgical masks
RR 0.7 [0.45, 1.1]3 studies · 7799 participantsVery low
Downgraded: risk of bias, imprecision, inconsistency
Viral respiratory illness ‐ influenza‐like illness
N95 respirators vs medical/surgical masks
RR 0.82 [0.66, 1.03]5 studies · 8407 participantsLow
Downgraded: risk of bias, imprecision
Viral respiratory illness ‐ laboratory‐confirmed influenza
N95 respirators vs medical/surgical masks
RR 1.1 [0.9, 1.34]5 studies · 8407 participantsModerate
Downgraded: imprecision
Adverse events
N95 respirators vs medical/surgical masks
no estimate extracted5 studies · 5 participantsVery low
Downgraded: risk of bias, imprecision, inconsistency

Hand hygiene compared to control for preventing the spread of viral respiratory illness

Population: general population and healthcare workers
5 questions
OutcomeEffectEvidenceStatus / GRADE
Acute respiratory illness
Hand hygiene vs control
RR 0.86 [0.81, 0.9]9 studies · 52105 participantsModerate
Downgraded: risk of bias
Influenza‐like illness
Hand hygiene vs control
RR 0.94 [0.81, 1.09]11 studies · 34503 participantsLow
Downgraded: risk of bias, inconsistency
Laboratory‐confirmed influenza
Hand hygiene vs control
RR 0.91 [0.63, 1.3]8 studies · 8332 participantsLow
Downgraded: imprecision, inconsistency
Composite of acute respiratory illness, influenza‐like illness, laboratory‐confirmed influenza
Hand hygiene vs control
RR 0.89 [0.83, 0.94]19 studies · 71210 participantsLow
Downgraded: risk of bias, inconsistency
Adverse events
Hand hygiene vs control
no estimate extracted2 studies · 2 participantsVery low
Downgraded: risk of bias, imprecision, inconsistency