What do systematic reviews say?

NIPPV vs NCPAP

Nasal intermittent positive pressure ventilation (NIPPV) may leads to lower chronic lung disease compared with nasal continuous positive airway pressure (NCPAP) (by population) (low certainty).

• Early nasal intermittent positive pressure ventilation (NIPPV) versus early nasal continuous positive airway pressure… 2023 · Cochrane Headline outcomes only
  RR 0.7 [0.52, 0.92]
  12 studies · 1284 participants
  Low

NIPPV vs NCPAP

Nasal intermittent positive pressure ventilation (NIPPV) showed no clear difference in pneumothorax compared with nasal continuous positive airway pressure (NCPAP) (by population) (low certainty).

• Early nasal intermittent positive pressure ventilation (NIPPV) versus early nasal continuous positive airway pressure… 2023 · Cochrane Headline outcomes only
  RR 0.92 [0.6, 1.41]
  16 studies · 1674 participants
  Low

NIPPV vs NCPAP

Nasal intermittent positive pressure ventilation (NIPPV) showed no clear difference in severe intraventricular hemorrhage (grade III/IV) compared with nasal continuous positive airway pressure (NCPAP) (by population) (low certainty).

• Early nasal intermittent positive pressure ventilation (NIPPV) versus early nasal continuous positive airway pressure… 2023 · Cochrane Headline outcomes only
  RR 0.98 [0.53, 1.79]
  8 studies · 977 participants
  Low

Medical/surgical masks vs no masks

Medical/surgical masks showed no clear difference in viral respiratory illness ‐ influenza/COVID‐like illness compared with no masks (moderate certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 0.95 [0.84, 1.09]
  9 studies · 276917 participants
  Moderate

Hand hygiene vs control

Hand hygiene showed no clear difference in laboratory‐confirmed influenza compared with control (low certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 0.91 [0.63, 1.3]
  8 studies · 8332 participants
  Low

Hand hygiene vs control

Hand hygiene may leads to lower composite of acute respiratory illness, influenza‐like illness,… compared with control (low certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 0.89 [0.83, 0.94]
  19 studies · 71210 participants
  Low

Hand hygiene vs control

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  no estimate extracted
  2 studies · 2 participants
  Very low

Medical/surgical masks vs no masks

Medical/surgical masks showed no clear difference in viral respiratory illness ‐ laboratory‐confirmed influenza/SARS‐CoV‐2 compared with no masks (moderate certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 1.01 [0.72, 1.42]
  6 studies · 13919 participants
  Moderate

Medical/surgical masks vs no masks

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 3 participants
  Very low

N95 respirators vs medical/surgical masks

It is very uncertain whether N95 respirators changes viral respiratory illness ‐ clinical respiratory illness compared with medical/surgical masks (very low certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 0.7 [0.45, 1.1]
  3 studies · 7799 participants
  Very low

N95 respirators vs medical/surgical masks

N95 respirators showed no clear difference in viral respiratory illness ‐ influenza‐like illness compared with medical/surgical masks (low certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 0.82 [0.66, 1.03]
  5 studies · 8407 participants
  Low

N95 respirators vs medical/surgical masks

N95 respirators showed no clear difference in viral respiratory illness ‐ laboratory‐confirmed influenza compared with medical/surgical masks (moderate certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 1.1 [0.9, 1.34]
  5 studies · 8407 participants
  Moderate

N95 respirators vs medical/surgical masks

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  no estimate extracted
  5 studies · 5 participants
  Very low

Hand hygiene vs control

Hand hygiene probably leads to lower acute respiratory illness compared with control (moderate certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 0.86 [0.81, 0.9]
  9 studies · 52105 participants
  Moderate

Hand hygiene vs control

Hand hygiene showed no clear difference in influenza‐like illness compared with control (low certainty).

• Physical interventions to interrupt or reduce the spread of respiratory viruses 2023 · Cochrane Headline outcomes only
  RR 0.94 [0.81, 1.09]
  11 studies · 34503 participants
  Low

Condiments/seasonings fortified with iron vs unfortified condiments/seasonings

It is very uncertain whether condiments/seasonings fortified with iron changes anaemia (defined as haemoglobin below WHO cut‐off for age and… compared with unfortified condiments/seasonings (very low certainty).

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  RR 0.34 [0.18, 0.65]
  4 studies · 2328 participants
  Very low

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

Condiments/seasonings fortified with iron plus other micronutrients may leads to lower iron deficiency (as defined by the trialists based on a biomarker of… compared with condiments/seasonings fortified with other micronutrients except iron (low certainty).

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  RR 0.36 [0.19, 0.69]
  4 studies · 1154 participants
  Low

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  5 studies · 1251 participants
  Very low

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  0 studies · 0 participants
  GRADE not reported

Condiments/seasonings fortified with iron plus other micronutrients vs condiments/seasonings fortified with other micronutrients except iron

• Fortification of condiments and seasonings with iron for preventing anaemia and improving health 2023 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 158 participants
  Low