Coverage is the simplicity or complexity with which the author explains the information.
How to determine coverage
1. Is the information provided simple or complex?
How long is the article? How extensive is the site? How much space is devoted to this subject? More credible information may be provided with more detail, which supports the facts or argument.
2. Are there links to other credible sites to learn more about the topic?
If there are, then coverage may be said to be better and the site is more likely to be credible.
3. Is there a reference list?
If there is (and the references are valid), then it is more likely that the site is credible.