Discovery Layers vs. the Traditional Catalog: e-Forum Summary
Erika Johnson and Kristin E. Martin
by discovery layer, the moderators were referring to the variety of tools available to libraries that bring together article-level content, specialized databases, and the content traditionally found inside a library catalog (e.g., books and journal titles) into a single searchable index. Based on the survey, 67% of e-forum participants are using a discovery layer and 83% maintain this layer alongside the traditional catalog. During the e-forum participants identified a number of commercial systems in use at their libraries (Summon, Encore, EDS, WorldCat Discovery, Primo), as well as some customized or open-source products. Participants at some specialized and public libraries expressed opinions that discovery layers do not fit their institutional needs, either because of the lack of sophisticated searching or specialized content, or because of overemphasis on article content.
In academic libraries, discovery layers tend to be the preferred tool for undergraduates, while more advanced scholars (and some library staff) prefer the traditional library catalog for known items, additional search features, and more specialized content. Discussion about the different levels of user sophistication and varying research needs continued through the entire e-forum. One participant put the difference between searching in terms of recall versus precision. Discovery makes an ideal tool for quickly returning at least some relevant results—great for basic research—but often brings back a large number of irrelevant results in a huge set.
From a technical services perspective, discovery layers have led to changes in technical services operations.
Discovery systems are not one size fits all. Special collections librarians and consortial members shared some concerns about the way discovery systems display information.
Good Question! What is a Discovery Layer?
Why is a discovery layer needed for libraries?
Without a discovery layer, users have to search many separate silos of information one by one – the library catalog for books and journals, publisher sites and individual ejournals in particular subjects for articles, and other specialized databases. Even for experienced users who know which databases and resources are likely to be most relevant to their needs, this is time-consuming and involves duplicating the same search over and over in different places. For novice users, or those who want a broad, interdisciplinary search, the initial choice of resource can be daunting and frustrating, unless users already know to ask their librarians for help. In addition, every database or resource interface is different – there are many similarities, but users have to learn different procedures and strategies for each information silo. While specialized interfaces deliver a lot of power for the advanced user, sometimes they can get in the way for other kinds of tasks.
Why not just use Google or another search engine?
Many library resources are difficult to find using search engines, even if a user is savvy enough to be using Google Scholar or Microsoft Academic Search instead of regular Google or Bing. In addition, almost all online library resources, such as full-text articles and ebooks, are most decidedly not free or open access – academic libraries pay quite a bit of money for them
more on academic libraries in this IMS blog