Evidence Based Librarianship

Evidence Based Librarianship

I saw that the Canadian Library Association has a SIG on EBL and am trying to figure out what exactly this is. From what I learned in my short bit of searching, it has developed out of health science or medical librarianship, but is being applied in other areas now. It is a framework for decision making by librarians, but other than this the definition used everywhere doesn't really help me:

What is EBL?

"Evidence-based librarianship (EBL) is an approach to information science that promotes the collection, interpretation, and integration of valid, important and applicable user-reported, librarian-observed, and research-derived evidence. The best-available evidence moderated by user needs and preferences, is applied to improve the quality of professional judgements."

- Andrew Booth
Exceeding expectations: achieving professional
excellence by getting research into practice.
LIANZA 2000

Further hints are welcome!