I don't see how they can determine how effective a vaccine is in such a short period of time,

[DetroitLegalBeagle]

10. Side effects are the concern, effectiveness less so

From my limited understanding on this, the effectiveness of the vaccine could be seen from the limited human testing that's going on, particularly with how easily spread COVID appears to be. Human challenge trials could prove it as well, but I don't think they are doing that since its ethically and legally a gray area. The bigger concern, that cannot be sped up, is side effects and long term effects. Side effects may not be seen until widespread use since a limited human trial may not represent the wide range of medical conditions and genetics that the population has. And long term issues with the vaccine is basically impossible since those won't be seen until months to years down the line.