"“As of now, two major ways the rate of myocarditis were minimized [during the presentation] was to lump people from age 39 and down –– even though the highest rates [of myocarditis] are in the youngest kids. This waters down the rate. The other method was to only include a very narrow window of time after vaccinations started in the 12-15 age group, thus omitting the vast majority of second doses, which is when about 75% or more of the myocarditis cases occur. Also, the genders were sometimes mixed. And rates in girls are much lower than boys.”
The article at The Defender goes into detail how CDC may have gamed the statistics to make them look less dangerous:
https://childrenshealthdefense.org/defender/link-heart-inflammation-pfizer-moderna-covid-vaccines-cdc-advisory/