Is the material up-to-date?
The best research draws on the most current work in the field. That said, depending on the discipline, some work has a longer shelf life than others. For example, important articles in literature, art, and music often tend to be considered current for years, or even decades, after publication. Articles in the physical sciences, however, are usually considered outdated within a year or two (or even sooner) after publication.
In choosing your materials, you need to think about the argument you’re making and the field (discipline) within which you’re making it.
For example, if you’re arguing that climate change is indeed anthropogenic (human-caused), do you want to use articles published more than four or five years ago? No. Because the science has evolved very rapidly on that question, you need to depend most heavily on research published within the last year or two.
However, suppose you’re arguing that blues music evolved from the field songs of American slaves. In this case, you should not only look at recent writing on the topic (within the last five years), but also look at historical assessments of the relationship between blues and slavery from previous decades.
Timeliness and Websites
Scrutinize websites, in particular, for dates of posting or for the last time the site was updated. Some sites have been left up for months or years without the site’s owner returning to update or monitor the site. If sites appear to have no regular oversight, you should look for alternative materials for your paper.