For graduate-level research you'll need to use specialized periodical databases that cover a specific subject. These list articles published in scholarly and peer-reviewed journals from around the world. Online periodical indexes (databases) may also link to the full text of the article.
Journal articles provide primary research, current information, and various points of view on your topic. Articles can also provide information about topics that are not covered in books. Search article databases, like the ones listed below, to find articles on your topic.
The most important databases for Physical Therapy are: