Hi Elizabeth --
The study to which I was referring compared the use of accessing digitized items via the EAD finding aid, versus searching for them individually. In this study, the items linked into the finding aid had minimal (auto-generated) MODS records, which pretty much only provided context, number of pages, and rights statements.
Focusing on testing our own interfaces is the primary way most usability studies have been performed, and it's an important start. Another level would be to test the findability in major search engines. A further level would be to study how researchers and scholars locate what they are seeking; I have seen only a couple of studies on this latter aspect. They seem to indicate that, as in seeking other answers, people turn first to those around them and to familiar sources. Secondarily, they may seek further (such as library databases); as a last resort (it seems) they contact librarians.
If this is really true, then it behooves us to make our content more findable in web search engines such as Google, using common search terms. Efforts I've seen in that direction utilize site maps, static browse interfaces that link into the databases, and schema.org encodings to help the search engine usefully index the contents of the pages crawled.
Jody L. DeRidder
Head, Digital Services
University of Alabama Libraries
Tuscaloosa, AL 35487
Phone: 205.348.0511