Statistics about vaccine use and consequences are playing a big part in contemporary debates about pandemic-related policies. Years ago, they also played a role in debates over the incidence and causes of autism. The current debate, like its precursor, suffers from confusion in the general public, and very likely confusion among scientists too, about how to categorize, communicate about, and even to think about risk.
Nate Silver, a statistician and special correspondent for ABC News, has complained that the FDA’s decision in mid-April to pause the distribution of Johnson & Johnson’s one-shot Covid vaccine was a terrible mistake, an overreaction to very rare events (blood clots in a handful of the recipients of the J&J shot) and one that was bound to cost lives by increasing vaccine hesitancy in the public.
In Pill Form:
The J&J decision arose in the context of cerebral venous sinus thrombosis (CVST). Fifteen people developed this rare form of blood clot after receiving the vaccine. This 15 is out of 8 million people in the US who have received the shot. This, in the eyes of the authorities, warranted a 9 day pause out of what was called “an abundance of caution.” A good sense of just what an outlier those 15 patients are is rare.