Question

A study was done to see whether a smaller dose of flu vaccine could be used successfully. in this​ study, the usual amount of vaccine was injected into half the​ patients, and the other half of the patients had only a small amount of vaccine injected. the response was measured by looking at the production of antibodies. in the​ end, the lower dose of vaccine was just as effective as a higher dose for those under 65 years old. what more do we need to know to be able to conclude that the lower dose of vaccine was equally effective at preventing the flu for those under​ 65?

Answer 1

The information that is needed to decide weather the lower dose of the vaccine was as effective at preventing the flu for people under the age of 65 is to know weather the patient was randomly assigned the lower dose or the full dose, if there was no randomization, it could mean there was bias which affects the conclusion. If there is randomization, it leads to the ability to discover causation.