Use these specialized encyclopedias similarly to the way you might use Wikipedia. They're a good a place to get a basic overview of an area and to find definitions for unfamiliar jargon. Some of them also provide basic quantitative data on a topic. Most of them will also have a bibliography that can point you to more good sources, many of which are likely to be scholarly.
Want to do research more efficiently? Start by reading a concise review of the research that's already been done on your topic!
