ab El'shina 1996.

Methods	Randomised controlled trial
Participants	432 healthy participants aged between 18 and 22 years who had not received any influenza immunisation during the previous 2 to 3 years.
Interventions	Polymer‐subunit influenza vaccine Grippol prepared with the strains A/Victoria/36/88, Wib ‐ 26, B/Panama 45/90. 2 types containing 5 or 2.5 µg haemagglutinin of each strain, respectively were compared with whole‐virion inactivated trivalent vaccine (reference preparation, containing 35 µg of haemagglutinin) and placebo (consisting of sterile physiological solution). One 0.5 mL dose was administered subcutaneously.
Outcomes	After immunisation, participants were placed under medical observation. Fever (48 hours follow‐up): weak (37.1 to 37.5 °C), moderate (37.6 to 38.5 °C), severe (> 38.6 °C). Systemic reactions (3 to 4 days follow‐up): feeling unwell, sore throat, hyperaemia of nasopharynx, head cold, cough, headache, blocked nose, dizziness, shivering, drowsiness, nausea, hoarseness. Local reaction: all (moderate weak); pain at site of injection.
Notes	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