[tired&retired]

This is a population analysis through a national database. It is not an experiment. Thus, the specific attributes of data variables may NOT be well defined.

You could say it is a correlational analysis which does not show cause and effect.

[dayglored]

> This is a population analysis through a national database. It is not an experiment. Thus, the specific attributes of data variables may NOT be well defined. You could say it is a correlational analysis which does not show cause and effect.

In which case, the title "Research Finds This Amount Of Coffee Can Adversely Affect Brain Health" is pure unadulterated BS clickbait.