There is an extremely large difference between taking an approved (with emergency authorization) vaccine and joining a research study where you could be getting

There is an extremely large difference between taking an approved (with emergency authorization) vaccine and joining a research study where you could be getting a different vaccine at earlier stages of approval or potentially a placebo. Joining a research study is great and helps push the science forward with other vaccines or whatever the researchers are studying, but it is not at all the same thing as scheduling when you are going to be getting an approved vaccine.