I have pointed this out before

The trials basically progress until a statistically significant number of the test participants return positive tests for the virus. Ideally, all of those 94 are from the placebo group and none from the vaccine group. In reality it is probably 80-90 from the placebo group and a handful from the vaccine group. They will also have data on how severe the relative cases were. For example, none of the vaccine group ended up in intensive care.

They have made this announcement now as they feel the data is statistically significant. They will keep on registering new cases to strengthen the case that the vaccine is effective.

Posted By: Timmy_Goat, Nov 9, 13:49:10