Inclusion and exclusion criteria
| Inclusion | Exclusion | |
| Population | Community setting (e.g. school, household, workplace, childcare centre, assisted living facility) | Healthcare workers (including dentists, mainly taking place in clinics) |
| Intervention | Any nonpharmaceutical intervention (e.g. facemask and variations, hand hygiene with soap, sanitiser or education, nasal or oral hygiene with over-the-counter products, school closure) | Pharmaceutical interventions (e.g. prescription medications, vaccines, professional oral hygiene, antiviral agents), surface or object disinfection Population-scale interventions (e.g. mass quarantine, airport screening, lockdowns, travel restrictions) |
| Comparison | No intervention or control | |
| Outcome | Self-reported or clinically diagnosed ARI, ILI, CRI Laboratory-confirmed influenza | Bacterial infection, fungal infection, parasitic infection |
| Language | English | Language other than English |
| Study type | Systematic reviews of interventional, observational, epidemiological studies | Nonsystematic reviews, systematic reviews containing modelling or simulation studies, umbrella reviews, meta-reviews |
| Time period | 1 January 2020 to 31 December 2020 | Before 1 January 2020 or after 31 December 2020 |
| Other | Must have at least two contributing authors | Single author, full text unretrievable |
ARI: acute respiratory illness; ILI: influenza-like illness; CRI: clinical respiratory infection.