ab Caplan 1977.

Methods	Randomised controlled trial to assess the reactogenicity and safety of monovalent whole‐virus and split‐virus vaccines prepared with strain A/Victoria/3/75 from different US manufacturers.
Participants	208 healthy adult volunteers aged between 18 and 64 years, recruited from the University of Maryland, USA.
Interventions	Monovalent whole‐virus vaccine (Merck Sharp & Dohme, Merrell‐National Laboratories) or monovalent split‐virus vaccine (Parke‐Davis and Company; Wyeth Laboratories) administered in different antigen concentrations (200, 400, or 800 CCA units) versus placebo. All from A/Victoria75. 1 dose intramuscularly.
Outcomes	Temperature >= 100 °F (37.8 °C), feverishness, pain or burning, tenderness, malaise or myalgia, nausea or vomiting, headache, other. 21‐day follow‐up. Safety outcomes are also given as cumulative % for each category: local, systemic, bothersome; febrile; or scores for systemic reactions.
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