Many health news stories lack independent sources

"News stories about medical research rarely include objective comments from experts who weren't involved in the work, according to a recent analysis.

Of nearly 600 news articles about medical research published in early 2013, only about one in six included a comment from a person not affiliated with the research - and a quarter of the independent sources quoted in the articles appeared to have no relevant expertise about the topic, the study found.

Also, the commenters frequently had conflicts of interest."