ab Langley 2005.

Methods	Randomised controlled trial
Participants	Healthy adults aged 18 to 50 years
Interventions	Inactivated A/New Caledonia/20/99 (H1N1) + A/Panama/2007/99 (H3N2) + B/Guangdong/120/2000 non‐covalent associated with outer membrane protein of Neisseria meningitidis. Single nasal dose containing 15, 30, 45 µg versus placebo (phosphate‐buffered saline) intranasally administered.
Outcomes	Local: within 7 days, graphic: rhinorrhoea, congestion, itch/burn, nosebleed, red/puffy eyes, sneezing, sore throat. Systemic: within 7 days: cough, shortness of breath, headache, muscle/joint aches, poor appetite, fatigue within 48 hours, nasal mucosa inflammation, nasal discharge, pharyngeal inflammation, sinusitis, enlarged cervical/postauricular nodes.
Notes	Safety data only were extracted. Government and industry funded
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Unclear
Allocation concealment (selection bias)	High risk	Inadequate
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Unclear
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Unclear
Summary assessment	High risk	High risk