ab Rocchi 1979a.

Methods	Cluster‐randomised controlled trial carried out during the 1976 to 1977 season
Participants	496 healthy military recruits (aged 18 to 20 years) belonging to 4 different companies from "Scuola Allievi Sottoufficiali" in Viterbo, Italy
Interventions	1 of the following 4 preparations were administered to 1 of the 4 study arms: 1. live attenuated A/Victoria/3/75; two 2 mL doses (2 104.5 EID50/dose) oral. 2. Live attenuated recombinant A/Puerto Rico/8/34, A/Victoria/3/75; two 0.5 mL doses intranasally (107 EID50/dose). 3. Inactivated A/Victoria/3/75 (600 IU), B/Hong Kong/5/72 (300 IU) and AlPO4, intramuscular placebo (vaccine diluent) administered intranasally. The 2 doses were administered 2 to 3 weeks apart.
Outcomes	Within 15 days after administration of the 1st dose. Malaise, myalgia, headache, sore throat, cough, fever >= 38.5 °C, fever >= 37.5 °C, 3 or more symptoms, any symptoms. Surveillance was passive.
Notes	Units of randomisation appear to be companies. No description of manner of allocation is mentioned. Blind (only for the cases of intranasal administration). Influenza outbreak occurred when the immunisation began (intraepidermic study). 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