Email: Nature vs. Encyclopaedia Brittanica [MG]
A study that lacks a rigorous method is no study at all.
Study methodology is something you learn in investigative journalism. Statistics lie when they're not employed by the book.
No study is valid without sound methodology, no study is valid without a statement of sample size and margin of error, and no study is valid by itself. It's popcorn journalism for anyone to say "A new study links XYZ with obesity..." because only a body of studies supporting a conclusion has any whiff of credibility.