Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Reference Coverage Analysis of OpenAlex compared to Web of Science and Scopus

Jack Culbert, Anne Hobert, Najko Jahn, Nick Haupka, Marion Schmidt, Paul Donner, Philipp Mayr

TL;DR

This study assesses OpenAlex as an open-source scholarly metadata provider by comparing its reference coverage and selected metadata to Web of Science and Scopus using a Shared Corpus of 16.8 million publications (2015–2022). It employs exact DOI matching to align records across databases and analyzes both coverage metrics and journal-level metadata, finding OpenAlex competitive with the proprietary sources for the core corpus, with high ORCID coverage but weaker abstract and funding metadata and similar Open Access indicators. The work highlights OpenAlex as a viable open alternative for reproducible bibliometrics within a core corpus, while cautioning about non-source reference gaps, data quality issues, and volatility as the database evolves. The findings emphasize the need for careful corpus selection and ongoing validation when using OpenAlex for scientometric analyses.

Abstract

OpenAlex is a promising open source of scholarly metadata, and competitor to established proprietary sources, such as the Web of Science and Scopus. As OpenAlex provides its data freely and openly, it permits researchers to perform bibliometric studies that can be reproduced in the community without licensing barriers. However, as OpenAlex is a rapidly evolving source and the data contained within is expanding and also quickly changing, the question naturally arises as to the trustworthiness of its data. In this report, we will study the reference coverage and selected metadata within each database and compare them with each other to help address this open question in bibliometrics. In our large-scale study, we demonstrate that, when restricted to a cleaned dataset of 16.8 million recent publications shared by all three databases, OpenAlex has average source reference numbers and internal coverage rates comparable to both Web of Science and Scopus. We further analyse the metadata in OpenAlex, the Web of Science and Scopus by journal, finding a similarity in the distribution of source reference counts in the Web of Science and Scopus as compared to OpenAlex. We also demonstrate that the comparison of other core metadata covered by OpenAlex shows mixed results when broken down by journal, capturing more ORCID identifiers, fewer abstracts and a similar number of Open Access status indicators per article when compared to both the Web of Science and Scopus.

Reference Coverage Analysis of OpenAlex compared to Web of Science and Scopus

TL;DR

This study assesses OpenAlex as an open-source scholarly metadata provider by comparing its reference coverage and selected metadata to Web of Science and Scopus using a Shared Corpus of 16.8 million publications (2015–2022). It employs exact DOI matching to align records across databases and analyzes both coverage metrics and journal-level metadata, finding OpenAlex competitive with the proprietary sources for the core corpus, with high ORCID coverage but weaker abstract and funding metadata and similar Open Access indicators. The work highlights OpenAlex as a viable open alternative for reproducible bibliometrics within a core corpus, while cautioning about non-source reference gaps, data quality issues, and volatility as the database evolves. The findings emphasize the need for careful corpus selection and ongoing validation when using OpenAlex for scientometric analyses.

Abstract

OpenAlex is a promising open source of scholarly metadata, and competitor to established proprietary sources, such as the Web of Science and Scopus. As OpenAlex provides its data freely and openly, it permits researchers to perform bibliometric studies that can be reproduced in the community without licensing barriers. However, as OpenAlex is a rapidly evolving source and the data contained within is expanding and also quickly changing, the question naturally arises as to the trustworthiness of its data. In this report, we will study the reference coverage and selected metadata within each database and compare them with each other to help address this open question in bibliometrics. In our large-scale study, we demonstrate that, when restricted to a cleaned dataset of 16.8 million recent publications shared by all three databases, OpenAlex has average source reference numbers and internal coverage rates comparable to both Web of Science and Scopus. We further analyse the metadata in OpenAlex, the Web of Science and Scopus by journal, finding a similarity in the distribution of source reference counts in the Web of Science and Scopus as compared to OpenAlex. We also demonstrate that the comparison of other core metadata covered by OpenAlex shows mixed results when broken down by journal, capturing more ORCID identifiers, fewer abstracts and a similar number of Open Access status indicators per article when compared to both the Web of Science and Scopus.
Paper Structure (13 sections, 4 figures, 4 tables)

This paper contains 13 sections, 4 figures, 4 tables.

Table of Contents

  1. Introduction
  2. Reference Coverage
  3. Open Metadata
  4. Data and Methodology
  5. DOI Match and Deduplication
  6. Error Margins of the DOI Match
  7. Metadata Coverage
  8. Results
  9. Total and Source Reference Coverage
  10. Discrepancies between Reference Counts and Reference Data
  11. Metadata by Journal
  12. Discussion
  13. Limitations and Outlook

Figures (4)

  • Figure 1: Venn diagram of the intersection sizes of unique DOIs based in each database on exact DOI match (without deduplication, i.e. cases of DOIs that have been assigned to multiple papers are now kept in the sets), for records published between 2015 and 2022.
  • Figure 2: Scatter diagrams of the count of source references per journal between OpenAlex and the Web of Science and Scopus.
  • Figure 3: Scatter diagrams of the count of source references per journal between OpenAlex and the Web of Science and Scopus.
  • Figure 4: Scatter diagrams of the coverage of metadata per journal between OpenAlex and the Web of Science and Scopus.