Opening the Gates: HKU Authors’ Odyssey in Open Access Publishing
— by Fanny Liu
Introduction
Similar to last year, this year we present an overview of open access publications by authors from the University of Hong Kong (HKU).
Data Source
Data were extracted from InCites on 11 February 2025. Publications included documents indexed in InCites Dataset (with ESCI) and with organization name “University of Hong Kong”. All Open Access encompassed Gold (including Gold Hybrid), Green and Bronze (Free to read) Open Access.
Altmetric reports were generated on 12 February 2025 with Altmetric Explorer.
All Open Access Publications
HKU authors have been committed to making their research outputs freely accessible. Between 2005 and 2024, there was an upward trend in the proportion of open access publications among all publications (Figure 1).
However, in 2024, the percentage significantly decreased by about 4.92% as compared with 2023. This might be caused by the shift of research focus from COVID-19 to other topics in the post-COVID-19 era. Previously, to accelerate research on COVID-19, various publishers made the relevant research articles freely accessible, while authors adopted preprinting (Besançon et al., 2021).
Figure 1: Percentage of All Open Access and Non-Open Access Publications by HKU Authors (2005-2024)
Gold and Green Open Access Publications
While the percentage of open access publications dropped significantly in 2024, the percentage of gold (including gold-hybrid) open access publications was on the rise (Figure 2). This might partly be enabled by the increasing numbers of Transformative Agreements, which helped HKU authors publish in gold open access in eligible journals without extra financial burden. For example, in 2024, the Libraries entered a Transformative Agreement with Springer Nature, which covered more than 1900 hybrid journals.
Publishers
In 2024, the publishers of journals with the highest number of publications in gold (including gold-hybrid) open access by HKU authors were Springer Nature (772 publications), Elsevier (532 publications) and Wiley (431 publications), together accounting for 52.77% of the publications. See Figure 3.
From 2025, the Libraries has entered new agreements with Elsevier and Oxford University Press, which cover selected hybrid journals. This could hopefully further support HKU scholars to publish in open access.
Citation Impact
The Category Normalized Citation Impact (CNCI) is calculated by dividing the number of citations by the expected citations to documents with the same document type, year of publication and subject area. The CNCI of a set of documents is the average of the CNCI values for all the documents in the set.
The CNCI values of all open access publications by HKU authors were consistently higher than non-open access ones, indicating the citation advantage of open access publications (Figure 4). Interestingly, the CNCI values of green only open access publications were the higher than gold (including gold-hybrid) ones. This might show that researchers did not have preference of gold open access publications over green ones when referencing previous literature.
Altmetrics
Among the non-open access publications with a DOI (digital object identifier) published by HKU authors in 2024 indexed by InCites and tracked by Altmetric Explorer, 58.65% received some kind of Altmetric attention, while 74.82% of all open access ones received mentions. On average, non-open access publications received 8.83 mentions, while all open access ones received 18.53 mentions. This might show that open access publications in general attract more social media attention and discussion.
The three non-open access and all open access publications receiving highest Altmetric Attention Scores are shown in Table 1.
| Non-open access publications | All open access publications |
|---|---|
Table 1: Three non-open access and all open access publications receiving highest Altmetric Attention Scores
The reports are available at:
- Non-open access publications: https://www.altmetric.com/explorer/report/ffb95f2b-1250-45bc-97ee-32bfa47b8143
- All open access publications: https://www.altmetric.com/explorer/report/ba17f6ce-073d-4f81-a2cd-7a4cb5aa6007
Conclusion
The uptake of open access by HKU authors has been evident over the past few years. Open access publications had clear advantages in both citations and social media attentions.
While green open access only publications may have higher citation impact than gold ones, researchers can actively consider depositing their publications in preprint servers or institutional repositories, especially when funding is not available for gold open access charges. The UNESCO Recommendation on Open Science (UNESCO, 2021) calls for investing in open science infrastructures and services. The Libraries will continue to develop the HKU Scholars Hub, HKU’s institutional repository, to cater for our researchers’ needs.
By embracing open science, we can create a more inclusive and transparent research environment that promotes the common good.
References
Besançon, L., Peiffer-Smadja, N., Segalas, C., Jiang, H., Masuzzo, P., Smout, C., Billy, E., Deforet, M., & Leyrat, C. (2021). Open science saves lives: Lessons from the COVID-19 pandemic. BMC Medical Research Methodology, 21(1), 117. https://doi.org/10.1186/s12874-021-01304-y
UNESCO. (2021). UNESCO Recommendation on Open Science. https://unesdoc.unesco.org/ark:/48223/pf0000379949
