Caveat emptor: Scan quality of Elsevier's digital backfile PDF collection

Scans of journal articles originally published in print, otherwise known as digital journal backfiles, benefit library patrons by providing near instantaneous access to important older information and full-text searchability. Digital backfiles can serve as a reliable surrogate for their corresponding print journals which could be removed from the library, freeing up space for other patron services. Both benefits are realized when the scanned articles are of sufficient clarity to replace the print versions. Several studies have analyzed small and subject-narrow sections of Elsevier's digital backfile. This article contains a scan-quality analysis from 1578 journals that contain nearly four million articles and represents a significant portion of Elsevier's entire digital journal backfile. We divided journals into three categories and five discipline-specific classifications and compared them by logistic regression for differences in scan quality. Approximately 4.2 % of the articles analyzed contained illegible text, tables, or figures. This data may inform a library's acquisition, retention and space-planning decisions that in turn will affect a patron's access to and use of electronic journal articles.