NAI30009.

Methods	Randomised, double‐blind, placebo‐controlled, parallel‐group multicentre study to investigate the efficacy and safety of zanamivir (GG167) 10 mg administered by inhalation twice daily for 5 days in the treatment of symptomatic influenza A and B viral infections in children ages 5 to 12 Location, number of centres: USA (36 centres); Canada (6); France (7); Germany (6); Belgium (2); Finland (2); Spain (2); Russia (2); Sweden (2); Israel (1) United Kingdom (1) Duration of study: 14 to 28 days
Participants	Children aged 5 to 12 years with influenza‐like illness (ILI)
Interventions	Zanamivir (5 mg per inhalation), 2 inhalations twice daily via Rotadisk/Diskhaler Placebo, 2 inhalations twice daily via Rotadisk/Diskhaler
Outcomes	Primary outcome: time to alleviation of clinically significant symptoms of influenza Secondary outcomes: Time to alleviation of clinically significant symptoms of influenza and no use of relief medication Time until the participant returned to normal activities Incidence of complications of influenza Antibiotic use for complications Mean overall assessment of diary card symptom score over post‐treatment Number of days out of study days 2 to 5 where cough was recorded Maximum daily diary card temperature Number of days out of study days 2 to 5 where the participant's parent recorded use of any relief medication Total number of 12‐hour periods during which supplied paracetamol was taken over the treatment period Total number of 12‐hour periods during which supplied dextromethorphan cough mixture (pholcodine in Europe) was taken over the treatment period Investigator Global Assessment of Symptoms at the study day 3 visit and at the post‐treatment visit Day 3 viral titre from throat swab Temperature as measured at the clinic visit on study day 3 for those participants with this assessment
Notes	Study conducted: 11 January 1999 to 19 April 1999. Different methods were used for allocation concealment in different countries
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Method used for sequence generation not specified
Allocation concealment (selection bias)	Low risk	An unblocked randomisation schedule was used. Eligible participants were allocated the next (i.e. lowest) sequential participant treatment number available at each centre
Incomplete outcome data (attrition bias) Symptoms	Low risk	ITT population included data for patients with missing diary cards
Incomplete outcome data (attrition bias) Complications of influenza	Low risk	ITT population included data for patients with missing diary cards
Incomplete outcome data (attrition bias) Safety data	Low risk	ITT population included data for patients with missing diary cards
Selective reporting (reporting bias)	High risk	Per‐protocol population not defined in the protocol
Other bias	High risk	Use of different relief medications across different centres
Blinding of participants and personnel (performance bias) All outcomes	High risk	No certificates of analysis were provided
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Only in the case of an emergency, when knowledge of the study drug was essential for the clinical management or welfare of the participant, could the investigator unblind a participant's treatment assignment. If the investigator broke the blind for an individual participant, the date and reason was recorded on the "status of treatment blind" page in the CRF. The investigator did not reveal the blind to the monitor