Clinical Study Types - for Librarians

There are several things to know about how to search PubMed for clinical trials and this section will discuss three of them:

1) "Publication Type" and "As Topic" for MeSH terms for clinical trials:  what are the differences between then and which is the best one to choose for locating clinical trials?  (answer: publication type)

2) "Clinical Studies" vs "Clinical Trials"   These are two separate filters; which is the best to use, and when?

3) "Epidemiologic Studies."  This is an important category that is NOT included in either Clinical Studies or Clinical Trials