Table 6 ALIC⁴E: oseltamivir in patients with influenza-like illness

Randomisation

“Stratified block randomisation was implemented, with random blocks of two, four, and six participants and stratification by age (< 12, 12–< 65, and ≥ 65 years), overall severity of influenza like illness (rated by the responsible clinician as mild, moderate, or severe), any relevant comorbidity (yes or no for heart disease, diabetes, chronic respiratory condition, hepatic, haematological, neurological, or neurodevelopmental condition, stroke or transient ischaemic attack, or overnight hospital stay in previous year), and previous duration of symptoms since onset (≤48 h or >48–72 h, based on recommendations that oseltamivir should be started within 48 h of symptom onset).”

Blinding

“This was an open-label study, so no placebo was used and drugs were not masked.”

“Some might consider the absence of a placebo control as a limitation. We deliberately chose to do an open-label trial in the context of everyday practice, because effect sizes identified by placebo-controlled, efficacy studies with tight inclusion criteria might not be reproduced in routine care. We also wished to estimate time to patient reported recovery from the addition of an antiviral agent to usual care rather than benefit from oseltamivir treatment compared with placebo. This pragmatic, open trial design makes our findings likely to reflect real world effects in primary care, because knowledge of what medication one is taking could affect subsequent help seeking and health behaviour and use of symptomatic medications. However, the design did not allow us to be sure of mechanisms or how much of the observed effect can be attributed to specific oseltamivir or other possible effects, and the relative contribution of such possible effects which might differ for the various subgroups.”