ab Zangwill 2001.

Methods	Randomised, placebo‐controlled trial to assess safety and reactogenicity of 4 different lots of cold‐adapted influenza vaccine. The aim of the study was to test replicability of lots vs placebo versus a different concentration.
Participants	Healthy children aged 12 to 36 months from the Kaiser Permanente paediatric clinic population. Children could be enrolled only in absence of the following conditions: hypersensitivity to eggs, presence of underlying chronic illnesses for which influenza vaccine was recommended, immunodeficiency diseases, acute febrile illnesses within 7 days or upper respiratory illnesses within 3 days of vaccination, prior receipt of inactivated flu vaccine or CAIV‐T, administration of an investigational drug within 1 month of vaccination in this study, administration of any live virus vaccine within 1 month of vaccination in this study, administration of any inactivated vaccine within 2 weeks of vaccination in the study, history of wheezing or bronchodilator medication use within 2 weeks before vaccination, receipt of any blood product within 3 months before vaccination, administration of nasal medication during the first 10 days after vaccination, no telephone in the household. 500 children were enrolled.
Interventions	Children were randomised into 5 groups to receive 1 of the following preparations. Groups 1, 2, 3: cold‐adapted trivalent influenza vaccine containing 107.0 TCID50 of each A/Shenzhen/227/95 (H1N1), A/Wuhan/359/95 (H3N2), B/Harbin/7/94 ‐like viral strains Group 4: cold‐adapted trivalent influenza vaccine containing 106.7 TCID50 of A/Texas/36/91 (H1N1), A/Wuhan/359/95 (H3N2), B/Harbin/7/94‐ like virus strains (same lot employed in the study of Belshe 1998) Group 5: placebo of egg allantoic fluid containing sucrose‐phosphate glutamate Each preparation was given as intranasal spray administered in 2 doses of 0.5 mL (0.25 mL per nostril) about 60 days apart. 500 children were enrolled; 474 children received 2 doses of vaccine or placebo.
Outcomes	Serological Paired sera for antibody response assessment Effectiveness N/A Safety After vaccination, children were observed for at least 15 minutes and families were provided with digital thermometer and diary cards to record temperature and occurrence of symptoms listed in the card (lethargy, irritability, runny nose/nasal congestion, sore throat, cough, headache, muscle aches, chills, vomiting) for 10 days. Other symptoms or medications taken were also reported.
Funding Source	Industry
Notes	The authors concluded that all lots of vaccines were safe and immunogenic. The number of children in each arm was not stated in the paper but was obtained through contact with author.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomisation list
Allocation concealment (selection bias)	Low risk	Coded
Blinding (performance bias and detection bias) All outcomes	Low risk	Double‐blinding
Incomplete outcome data (attrition bias) All outcomes	Low risk
Summary assessments	Low risk	Plausible bias unlikely to seriously alter the results.