[pepperberg]

I have one question regarding the current data (it would be great if anyone with experience in statistics could help out):

The FDA document (p. 26, table 8) states that the vaccine efficacy (age group >=75) is 100.0% (95% confidence interval of -12.1 to 100.0).

What does this mean? With my limited university statistics class knowledge I would say they are 95% sure that the efficacy lies between -12.1% and 100.0% for age >=75.

Is this the correct interpretation? If yes, doesn’t it show that we simply do not know about its efficacy in this age group yet (due to lack of data)? If not, could you please explain it?

Thank you in advance!