Response to Argument Against COVID-19 Vaccine Absolute Risk Reductions

Response to Argument Against COVID-19 Vaccine Absolute Risk Reductions

A commentary published on, April 29, 2021, claims that COVID-19 vaccine clinical trials were too brief to judge outcomes using absolute risk reductions (ARR), and that extending a clinical trial’s length of time can increase the ARR, thereby reducing the number needed to vaccinate to prevent one infection. Why Number Needed to Treat Can Be Misleading for Vaccines ( The author’s argument in the commentary may be technically correct under certain assumed conditions or considered “contextual points,” but the argument is clinically meaningless at best.

The Pfzier/BioNTech vaccine’s absolute risk reduction is 0.7%, and the vaccine efficacy or relative risk reduction (RRR) is 95.1% Medicina | Free Full-Text | Outcome Reporting Bias in COVID-19 mRNA Vaccine Clinical Trials ( Published results from the Pfzier/BioNTech phase 3 clinical trial covered the period from May 2020 to November 2020, having a trial length of 6-7 months; more than just “a few weeks” claimed by the commentary. Inside the Pfizer/BioNTech COVID-19 vaccine trial: Insights on speed, agility and digital development (

To follow the author’s argument in the commentary, let’s double the Pfzier/BioNTech phase 3 trial from seven months to 14 months, and also assume that cases in the vaccine group and the placebo group double. Under these circumstances, as the author indicated, the ARR will now double from 0.7% to 1.4% while the RRR remains the same at 95.1%. But how much has the ARR improved compared to the RRR? Not much. Let’s double the cases and trial time again. The ARR at 28 months is now 2.8% compared to the RRR of 95.1%…still pretty low. Get the point? The effect of length of time on the ARR compared to the RRR is relatively meaningless from a clinical and public health point of view. 

Just out of curiosity, how long would it take for the ARR to catch up to the RRR under these “contextual” conditions? At 56 months the ARR is 5.6%; 112 months: 11.2%; 224 months: 22.4%; 448 months: 44.8%; 896 months: 89.6%…it would take over 75 years for the ARR to reach the RRR level under assumed conditions of consistent vaccine efficacy!

But let’s get back to reality. The more important point is that the relative risk measures, ARR and RRR, are both valid only for the actual length of the clinical trial. One cannot assume that the effectiveness of the vaccine in the “real world” would continue at the same efficacy rate beyond the trial length without supporting evidence. If you think you might get a better ARR with a longer trial, then the only proof is a longer trial. But basic principles of pharmacodynamics suggest the opposite is just as likely to occur. 

Pharmacotherapies have limited real life effectiveness over time, including vaccines for influenza-like illnesses. Pharmaceutical companies rely on time-limited benefits to promote annual sales of seasonal influenza vaccines and booster shots. Additionally, the mRNA vaccines’ alleged biological mechanism of stimulating additional spike protein biosynthesis can theoretically only provide therapeutic benefits as long as the additional spike proteins remain active in the body. No protein remains in the body indefinitely as proteins are eventually catabolized and eliminated.

In conclusion, the argument in the commentary, that a vaccine’s ARR increases indefinitely with increasing length of time, is invalid because it assumes vaccine efficacy will continue at the same rate beyond the clinical trial length, without providing any strictly controlled experimental evidence to support this assumption. 


  1. Thanks Ron. It is clear what the ARR is now.

    What do you think a good ARR is for a vaccine? Can you quote ARR the best and the worst of vaccines (other than COVID-19 vaccines) as a basis for comparison? For example: MMR, H1N1, PCV13? (I just don’t know where to look for these figures. I want to be able to put your calculation into the context of what has been achieved with other vaccines)

  2. …and so the intellectual debate quickly fades away in the face of an onslaught of emotional invective.
    Thank the gods for courts and judges, where this sort of behavior is quickly met by admonishment, a contempt order, a stiff monetary fine, community service — and occasionally — involuntary confinement in an 8′ x 12′ room with a magnificent view of a hallway wall.

  3. Ron makes an excellent and easy to understand argument which must be attacked and covered up by experts for this fakedemic to continue beyond any reasonable doubt.
    Let’s observe what is happening with Fauci and friends, and their apparent destruction as traitors and purveyors of bioweapons.
    If only there is some……😎

  4. Perhaps a good way to look at it is what happens to case numbers and case fatalities before and after the vaccine is applied. Going by the case numbers from Israel, the mRNA vaccines do appear to be effective. Time will tell.

    1. in what way can vaccines be linked to PCR-determined cases? Only in a fantasy land of fuckccemia!
      Only a fool can consider PCR DNA factory as a test for ANYTHING, and only a mega full can claim that the “lucky spike” FUCKCINES can prevent ANYTHING considering that the clinical end points DID NOT AIM AT PREVENTING but at lower severity and duration of symptoms!!! Any fools around?