ca Vasil'eva 1982.

Methods	Comparative cohort study of a monovalent injected vaccine in children aged 7 to 15 years in Leningrad, former USSR. The setting, season, and viral circulation are not described.
Participants	335 children of unknown provenance
Interventions	Monovalent inactivated vaccine containing A/Texas/1/77 (H3N2) (Leningrad Louis Pasteur laboratories) subcutaneous or by needleless injector or placebo. Placebo is not described.
Outcomes	Serological Paired sera taken in an undescribed fashion. There were antibody rises to other influenza A viruses and PIV 1 in the placebo arm. Effectiveness Influenza‐like illness described in the translation as "influenza and URTI". Breakdown by age groups and type of injection is not reported. Safety Temperature, induration, headache, malaise, sore throat. Daily physical examinations for 5 days.
Funding Source	Unclear
Notes	The authors conclude that the vaccine (incidence in the arms was 1.8 and 9.9, respectively) was effective, immunogenic, and safe. Very brief report. There is no description of randomisation, allocation, or attrition. The authors briefly described evidence of A/Khabarovsk/77, A/Texas/77, and PIV 1 circulation in the placebo arm, which could account for some of the febrile episodes.
Risk of bias
Bias	Authors' judgement	Support for judgement
PCS/RCS‐Selection Exposed cohort	Unclear risk	Not described
PCS/RCS‐Selection Non Exposed cohort	Unclear risk	Not described
PCS/RCS‐Comparability	Unclear risk	Not described
PCS/RCS‐Assessment of Oucome	Unclear risk	Not described
Summary assessments	High risk	Insufficient information to assess study design