3 ms·the covid vaccine trials had no control groups eitherby a45a33s 5y agothe covid vaccine trials had no control groups eitherrsfern 5y agoThey were all doubly blinded placebo controlled trials… Are you talking about how they unblinded the study after efficacy results started coming in?a45a33s 5y agoyes i am talking about how they got rid of the control groups once it appeared to be working