Oxford, AstraZeneca differ on how they found 90% effective vaccine dosing pattern

AstraZeneca and Oxford University have given conflicting versions of how they came upon the regimen of half a dose followed by a full dose for their COVID-19 vaccine. The half-dose pattern was found to be 90% effective. While AstraZeneca said the half-dose was given inadvertently to some participants, an Oxford scientist said the shot was given deliberately after thorough consultations.