ab Atmar 1990.

Methods	Double‐blind, placebo‐controlled, randomised trial
Participants	74 healthy volunteers aged 18 to 40 years (data on 17 asthmatics were not extracted)
Interventions	Cold ‐ recombinant vaccine A (H1N1) (n = 16) versus cold ‐ recombinant vaccine A (H3N2) (n = 13) versus cold ‐ recombinant vaccine B (n = 17) versus placebo (n = 26) Intranasal
Outcomes	Pulmonary function tests (performed on days 0, 3 to 4, 7 after vaccination): FEV1 FVC FEV1/FVC Forced expiratory flow rate 25% to 75% (FEF 25 to 75)
Notes	The authors report several non‐significant drops in FEV and FVC up to 7 days' postinoculation and a higher incidence of ILI (17/46 versus 4/26) in the vaccinated arms. Safety data only were extracted. Government funded
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Unclear
Allocation concealment (selection bias)	Unclear risk	Unclear
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Unclear
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Unclear
Summary assessment	Unclear risk	Unclear