WorldCat: Can it be the best collection evaluation tool?

Many collection evaluation methods were used in the past, yet none of them can be considered highly reliable. The most popular technique was the checklist method which consists of comparing the library holdings to a particular bibliography. However, the limitations of this method overcome its advantages since the generated numbers are difficult to interpret, the list can be outdated, and the items on the list may not match the curriculum of the institution in a particular subject area. Other methods include citation analysis, surveys, and circulation studies.
Jennifer McClure employed a relatively new method based on the WorldCat database to evaluate the effectiveness of three foreign approval plans for romance languages (French, Spanish, and Italian) at the University of Alabama libraries. This method consists of comparing a library’s collection in a particular subject to other libraries’ collections available through WorldCat. It is very similar to the checklist method, yet it has more advantages such as the ability to limit the search by date, genre, form, language, and audience. Also, WorldCat has the capacity to compare a library’s collection to different libraries at the same time which make the comparison list more exhaustive. McClure stated that the goal of the assessment project is to compare the three approval plans separately to the universe of possible acquisitions represented by the collections of four prominent universities. Some technical flaws appeared during the search process. The search by LC call numbers was problematic since the truncated search generated items that are not required and excluded other required records. The results were surprising. Among the three collections, the library owns the highest percentage in the least important language in the library’s collection development policy and vice versa. Yet, McClure discovered the importance of the first 100 titles retrieved from WorldCat and arranged by the number of holdings. McClure concluded that these titles represent the core collection of the curriculum and should be purchased by the library.
The effectiveness of WorldCat as an assessment tool is derived from its strong collection as a union catalog that contains almost every published book in any discipline. This characteristic makes any checklist generated from WorldCat exceptionally thorough. Also, the easiness of comparison of library holdings in a specific field to many other libraries within a reasonable time frame is another advantage of WorldCat. Yet, as in the classic checklist method, it is both difficult to interpret the results, and challenging to determine if the collections of the comparison libraries are similar or close to the library compared.

McClure, Jennifer (2009). "Collection Assessment through WorldCat". Collection management (0146-2679), 34 (2), p. 79.