> The study gives you the actual numbers on how likely it's a coincidence or not.
The study doesn't really do that. What it does is compare different methodologies for counting the number of incidences of (myo|peri)-carditis following the 2nd shot. They conclude that the methodology used officially gives lower numbers than other methodologies.
Counting how likely a coincidence it is is something we can do reasonably well using standard null hypothesis testing: compare the number of incidences of pericarditis in a random sample against a sample of patients post-vaccine. But this is not something that the article does. The difficulty, discussed in the article, lies in deciding what counts as "post-vaccine".
The study doesn't really do that. What it does is compare different methodologies for counting the number of incidences of (myo|peri)-carditis following the 2nd shot. They conclude that the methodology used officially gives lower numbers than other methodologies.
Counting how likely a coincidence it is is something we can do reasonably well using standard null hypothesis testing: compare the number of incidences of pericarditis in a random sample against a sample of patients post-vaccine. But this is not something that the article does. The difficulty, discussed in the article, lies in deciding what counts as "post-vaccine".