The researchers note that their study has several limitations, including the chance that political party affiliation "is a proxy for other risk factors," such as income, health insurance status and chronic medical conditions, along with race and ethnicity.....
...The researchers' data also did not specify a cause of death, and it accounts for some 83.5% of U.S. deaths, rather than the entire number. And because data about the vaccination status of each of the 538,159 people who died in the two states wasn't available, researchers could only go as granular as the county level in assessing excess deaths and vaccination rates.