One question you should always ask is, "who wrote it?" With the explosion of online information there are millions of authors on a countless number of topics. When you are looking at any material you should first identify who the author is, and how they are qualified to write on this topic. Normally, at the first page of a journal article, you will see what their day job is underneath their name and title.
Below is an example of author information within a journal article:
You can see the authors' name are:
At the bottom you can see their places of employment:
If you cannot easily identify this information it is not a journal article, but some other type of material. Remember that you are a detective and should do some sort of evaluation for every resource you locate.
Another important thing to note in your evaluation process is to identify the audience. This is especially important in the health sciences as some material is clearly written for consumers, while others is written for professionals.
The material below is written for consumers:
The material below is written for professionals:
Notice the difference in language.
If the purpose of your project would be to educate a patient on a topic you would refer to the first article. However if you are doing a professional project, you would use the second one. With these examples you can see how information is not one size fits all.