Clarifying COVID data

Re: Study warns not to delay second Pfizer dose, Tom Blackwell, Feb. 3

As a former post-doctoral research immunologist at Scripps Research Institute, I believe it is essential to clarify two distinctions to better understand the controversy regarding COVID-19 vaccine dosing.

First is the differentiation between experimental laboratory science, which seeks truth through strict methodology, observation, and inference, and mathematical modelling, which provides forecasts through theoretical arithmetic calculation.

Published data concerning vaccine efficacy from the Pfizer and Moderna trials arises from experimental science, whereas long-term effectiveness projections for single-dose vaccinations are derived from non-experimentally observed results postulated by mathematics.

Second, it is crucial to distinguish between the science of randomized controlled clinical drug prevention trials and the art of managing a public health crisis in the context of a clear shortage of vaccines.

The scientific data that support the efficacy and safety of both vaccines is very limited and cannot be validly extrapolated by use of mathematics. Policy-makers should be clear about what we know, whether it is derived from experiment or arithmetic calculation, and to what degree vaccine policies are based upon speculation.

Stephen B. Sinclair, Richmond Hill, Ont.

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