Taking data for a whole country and drawing conclusions about a specific region may not be so good. For example, in the paper there is a lot of talk about bad data in the US but when they turn to the blue zone in the US there is no issue with the data. It's considered well kept.
For other places, like Sardinia, they don't explain whether the variations (1st of a month, etc) are happening at the local level. Can the data there be trusted? We are left to draw conclusions because many gaps aren't explicitly filled in.
The blue zones project limited the places they would label a blue zone to those that had good data. Many places were rejected because the data wasn't good. Looking at those places, like the UK or France, and stating they have untrustworthy data actually confirms the blue zones work of rejecting claims there due to untrustworthy data.
mfer|2 years ago
For other places, like Sardinia, they don't explain whether the variations (1st of a month, etc) are happening at the local level. Can the data there be trusted? We are left to draw conclusions because many gaps aren't explicitly filled in.
The blue zones project limited the places they would label a blue zone to those that had good data. Many places were rejected because the data wasn't good. Looking at those places, like the UK or France, and stating they have untrustworthy data actually confirms the blue zones work of rejecting claims there due to untrustworthy data.