What Are We Missing? A Systematic Approach to Overlap Analyses of Local and Global Repositories

Local repositories, managed by institutions, often differ in coverage and metadata from the research output affiliated with the concerned institutions in global repositories such as OpenAlex, which aggregate records from numerous sources for broader visibility. This paper introduces a DOI Screening System that systematically identifies and explains mismatches between local and global repositories by classifying publications as local-only, matched, or global-only. The system applies predefined rules and allows identifying patterns such as misattributed affiliations, unrecognized DOI prefixes, incomplete metadata, or underrepresented publication types. Based on these patterns, one can derive ‘curative’ actions. We demonstrate the system’s utility by comparing the repositories of EPFL and of ETH Zurich to OpenAlex, showing how subtle inconsistencies in identifiers and affiliations can account for many discrepancies. The system provides insights into how targeted interventions addressing the root causes of these discrepancies can be used to enhance coverage and reliability in both local and global repositories.