Judging the Need for and Value of DDA in an Academic Research Library Setting
This article reports findings from a multiphase analysis of demand-driven acquisitions (DDA) within the academic research library setting. Evaluating local collections within the context of Trueswell’s (1969) often-cited 80/20 Rule, phase one of this study illustrates the deficiencies of a just-in-case approach to building library collections. Following from this, phase two evaluates the viability of DDA as the just-in-time collection-building solution librarians have sought as an answer to low-use titles that plague most academic library collections. Supported by 16 months of data, this study scrutinizes the comparative value of DDA against traditionally acquired titles along two key dimensions—the subject-matter profile of purchases and their overall usage levels. Further, the concept of a utility as value paradigm, as well as a purchase use equilibrium for library collections, provide a theoretical framework in which the relative value of DDA is assessed. From a content, or subject-matter, perspective, this study finds negligible deviation in those purchasing patterns associated with DDA when compared with traditionally-acquired materials. At the same time, DDA titles experience much higher levels of use and are, therefore, associated with markedly lower cost-per-use figures and greater overall value.