Sometimes, a quick visual check may convince you that an article is a scholarly or even a peer-reviewed one.
What do you notice about the following excerpts from JAMA (Journal of the American Medical Association)?
Hopefully, you noticed the authors' affiliations, their credentials and the structured abstract.
What about this one from the Journal of the American Medical Informatics Association?
Hopefully, you noticed the received & accepted dated. These dates reflect the peer-review process the article went throught before being published. As you can see, there was some time between those 2 dates. Did you also notice the structured abstract, the author affiliations and credentials?
Want to double check that journal? Search Ulrich's and when you see the little "referere shirt" icon, you'll know it is a scholaly peer-reviewed journal. Note: article types matter, so a letter to the editor is not really scholarly as say an an article about someone's research.