To get a better understanding of any research topic, it is helpful to determine the main concept(s) involved, and then find encyclopedia entries on that concept. This will not only give you an historical context (how has the thing, theory, or technology evolved over time?, what people, laws and policies are involved? etc.), but will also help you locate the best key words that are essential when searching the scholarly literature. Once you have a handle on your concept(s) using the specialized encyclopedias, use that background knowledge to search the journal, book and other scholarly and professional literature, using some of the search tools listed in the "Information Sources" section below.
Choose a search tool from those listed below. CINAHL is the best resource for nursing-specific literature, but you may want to try others, such as MEDLINE for topics that cross into more general health and medicine fields.