Diamond Open Access Landscape in Croatia: DIAMAS Survey Results ^†

Abstract

As open science initiatives address the crisis in scholarly communication driven by commercialisation, diamond open access publishing—promoting equity for authors and readers—has emerged as a focal point in open access scholarly publishing. This study examines the landscape of institutional publishing in Croatia, focusing on the community-owned diamond open access model. Through the DIAMAS project survey, which targeted 251 institutional publishers and achieved a response rate of 77, the research identifies the distinct features of Croatian institutional publishing. Institutional publishers are characterised by governance structures, funding challenges, voluntary staffing, and alignment with open science principles. Notable traits include reliance on public funding, use of the national open access journal platform, and a strong diamond open access publishing tradition. Key findings emphasise the critical role of national infrastructure, services, and multilingual publishing. Persistent challenges include meeting indexing criteria, advancing open science practices, and ensuring metadata quality. This study provides a comprehensive mapping of Croatian institutional publishers, offering insights into their strengths and weaknesses while proposing strategies for improvement. The findings underscore the importance of national policy frameworks, capacity building, and international collaboration to ensure the sustainability and visibility of Croatian institutional publishing.

1. Introduction

In addition to promoting high-quality research, the core values of the open science movement include universal open access (OA) and collective welfare. These principles dictate that scientific practices should be inclusive, sustainable, and equitable, ensuring fairness among researchers (UNESCO, 2021). While open access has significantly increased the availability of research methods and results, the current business models employed by major publishers do not provide equal publication opportunities for scientists, nor do they uphold the same levels of integrity for scientific publications from smaller or less developed countries. This situation suggests an ongoing colonisation of scientific publishing and open access (Khanna et al., 2022).

Research suggests that many journals from these countries remain unindexed in prominent databases (Raza et al., 2024). To advance global equity and foster epistemological diversity in knowledge production and consumption, a shift from the gold open access model—characterised by high publication fees (Borrego, 2023)—to the diamond model (Druelinger & Ma, 2023) is essential. While the diamond model is commonly understood as one in which neither authors nor readers pay fees, its implementation is more complex. In some regions, the diamond model is deeply embedded in the publishing tradition, while in others, it has only recently been introduced as the primary publishing method (Mahony, 2024). Meanwhile, some countries are still experimenting with this approach. These varying levels of adoption have resulted in diverse characteristics in diamond publishing, such as governance structures, cost-sharing arrangements, workforce requirements, editorial management, alignment with open science principles, publication languages, visibility, and technical support services.

Moreover, the success of the diamond model is closely tied to the research assessment systems in place. Despite its clear advantages, diamond open access publications are often undervalued in research evaluations (Liu, 2024). Addressing all these complexities at the 2nd Diamond Open Access Conference, seven key facets of diamond open access were identified: (1) equity, (2) knowledge as a public good, (3) community-driven initiatives, (4) diversity, (5) transitioning to diamond, (6) research assessment and recognition, and (7) multi-level cooperation (Saenen et al., 2024). Thus, studies that examine the intricate nature of diamond publishing are highly valuable.

Locally published scholarly journals play a crucial role in small and developing countries, primarily by safeguarding the quality of locally relevant research, as outlined in the Leiden Manifesto (Hicks et al., 2015). They foster the development of non-English terminology in various scientific disciplines. They promote using the native language in scientific discourse, facilitating access to research findings for the broader local community without language barriers. Although research shows that non-English journals generally have a lower global impact in terms of citation counts (Yoon et al., 2023), prioritising linguistic accessibility enhances scholarly communication and knowledge dissemination within local contexts, thereby fostering greater stakeholder engagement and understanding.

Furthermore, they offer invaluable support to early career researchers by providing closer editors’ guidance and collaboration throughout the publishing process, actively contributing to the enrichment of research and academic culture, bolstering the reputation of the local scholarly community and shaping the criteria for assessment in the academic sphere. These journals also highlight the significance of impact beyond mere citation numbers, allowing scientists to disseminate their work without the exorbitant fees often associated with prestigious “gold” journals (Druelinger & Ma, 2023). Local scholarly publications bridge the divide between scientific advancements and societal applications by emphasising ethical considerations and research integrity.

Croatian scholarly publishing has a long history, dating back to the first scholarly journal, “Arkiv za povjestnicu jugoslavensku” (Archives of South Slavic History) in 1851 (Hebrang Grgić, 2018). The specifics of the Croatian publishing landscape set it apart from the prevailing models in journal publishing, which are often characterised by profit-driven approaches, high prices, monopolies, paywalls, digital divides, and English language dominance. In Croatia, scholarly journals are primarily published by universities and learned societies committed to a diamond, non-profit business model, a critical factor in the early adoption of open access principles. This commitment led to the founding of the Portal of Croatian Scientific and Professional Journals (HRČAK) in 2006, a comprehensive national platform hosting Croatian open access journals.

As of the writing of this article, HRČAK hosts more than 500 Croatian scholarly, professional, and popular open access journals, including more than 400 active journals, which collectively store almost 300,000 published articles. State subsidies to journals support the diamond open access publishing model, which is contingent on open access and the inclusion of the subsidised journal in HRČAK. Only a few Croatian journals utilise the ‘article processing charges’ (APC) model, underscoring the community’s dedication to the unrestricted dissemination of knowledge. Although state subsidies are insufficient to cover all publication costs, a significant share of volunteer work and institutional support enables the publication of many scholarly journals.

In contrast to Croatia’s thriving open access journal scene, the transition towards OA publication of books and monographs has been more cautious, with only a limited number of active academic publishers engaged in this endeavour. Unlike journal publishing, state book subsidies do not typically incentivise open access. A possible explanation is that these subsidies are often directed towards small commercial publishing houses, which heavily rely on such financial support for their sustainability, regardless of their OA policies. Nonetheless, certain universities have initiated establishing publishing platforms dedicated to releasing open access books and conference proceedings.

Despite various studies examining Croatian journals, the focus has predominantly been on bibliometric analyses of individual journals (Silva de Araújo et al., 2020; Marijan, 2019; Dabić et al., 2021; Wang et al., 2020) or a set of journals (Moslavac, 2022), with limited research covering the analysis of state subsidies (Sambunjak et al., 2008; Macan & Stojanovski, 2008). To our knowledge, comprehensive research on the Croatian open access publishing landscape appears absent, indicating gaps in understanding and documentation. Therefore, this paper aims to map the Croatian publishing landscape, focusing on institutional publishers and the diamond open access model. The main research question was what are the key characteristics of Croatian institutional publishers and service providers (IPSPs) regarding governance, funding, staff, services, publications, and open science practices, and how do these impact editorial quality and management, technical services efficiency, and visibility?

This question was further divided into the following subquestions:

• What types of institutions and governance models are predominant among Croatian institutional publishers, and how active are they in local and international professional circles?
• What are the primary funding sources for Croatian institutional publishers, and how many staff members do they employ?
• What range of services, types of publications, and languages do Croatian institutional publishers offer and use?
• To what extent do Croatian institutional publishers implement open science practices?
• How do Croatian institutional publishers ensure editorial quality and uphold research integrity?
• What technical services do Croatian institutional publishers provide, and what are their main challenges?
• What strategies do Croatian institutional publishers employ to improve the visibility and impact of their publications?

As part of the Developing Institutional Open Access Publishing Models to Advance Scholarly Communication (DIAMAS) project, a thorough survey was conducted across 45 European countries, including Croatia, garnering significant participation from institutional publishers and editors (Armengou et al., 2023). Primary survey outcomes specific to Croatia have been detailed in this paper, with the broader findings integrated into the comprehensive reports “Institutional Publishing in the ERA1: Results from the DIAMAS survey” (Armengou et al., 2023) and “Institutional Publishing in the ERA: Full Country Reports” (Agnoloni et al., 2024).

Croatian organisations participating in the DIAMAS project are the University of Zadar and the University of Zagreb Faculty of Humanities and Social Sciences.

2. Materials and Methods

DIAMAS IPSP survey was conducted between 29 March and 10 May 2023. The survey focused on institutional publishers and service providers (IPSPs) as a target group rather than on individual journals. Two complementary types of IPSP are distinguished: institutional publishers (IPs), who carry legal, ethical, or scientific responsibility for academic publishing, and service providers (SPs), who have more limited responsibility for specific activities in the publishing process (Armengou et al., 2023). Both types can be integrated into a single IPSP. DIAMAS defined institutions as research-performing institutions, research-funding institutions, scholarly/learned societies, and academies (Bargheer et al., 2023).

The survey questions were structured in nine groups as follows (DIAMAS, 2024):

• Introductory questions—identification;
• Introductory questions—demographics;
• Funding;
• Ownership and governance;
• Open access and open science practices;
• Editorial quality, editorial management, and research integrity;
• Technical service efficiency;
• Visibility, including indexation;
• Equity, Diversity, Inclusion, and Belonging (EDIB): multilingualism, gender equity, and accessibility.

Before dissemination, limited face validity and full testing were conducted to check questions’ clarity and collect feedback. According to the testing results, some questions were corrected, and one-third were deleted to avoid a high dropout rate. To ensure the best possible accessibility and to receive as many responses as possible, the final English version of the survey (DIAMAS, 2024), containing 59 questions in nine groups, was translated into Croatian by corresponding project members.

The survey invitations were distributed via Qualtrics, an online survey tool, between 29 and 31 March 2023. Croatian project members also sent individual invitations to identified IPSPs, followed by two reminders. Additionally, the survey was disseminated through existing Croatian mailing lists, targeting editors, publishers, and libraries. It remained open until 10 May 2023. Informed consent was obtained from all participants through an integrated statement in the introductory section of the survey, as documented in the Survey Questions Data Description within the available dataset (Kramer & George, 2024).

The DIAMAS survey targeted 251 Croatian IPSPs and achieved a response rate of 77, the second-highest among the 45 ERA countries participating in the DIAMAS study. Croatian project partners identified contacts for 228 IPSPs using data from the HRČAK platform and 23 from external resources. While service providers (SPs) can be distinct entities from institutional publishers (IPs), most respondents identified themselves as institutional publishers that also provide services. Consequently, IPSPs were treated as the unit of analysis without differentiating between IPs and SPs.

Several limiting factors necessitate caution when generalising the findings to the broader population of IPSPs. These include the relatively low response rate compared to the number of invitations sent, ambiguities in question wording, and challenges in translating the survey content from English to Croatian. This data collection, analysis, and report serve as a foundational effort, offering essential insights and highlighting areas for further investigation and improvement.

3. Results

3.1. IPSP Profiles, Governance, and Membership

We gathered identifying information from introductory identification and demographic responses such as IPSP official names in Croatian, translated names, contact and respondent names and email addresses, respondent function, website URLs, and contact permissions. This information allowed us to access IPSP identification and additional data collection by checking their websites. Among 77 respondents, we identified five types of IPSPs: university/faculty (21, including 4 universities with dedicated web pages for their publishing activities), learned society/association (18), research institute (6), library (3), and museum (3). Still, 22 respondents identified themselves as a single journal. The rest of the respondents reported that national publishing platforms (1), library repositories (1), and publishing houses (1) were IPSP types. The responses on the respondent’s function revealed seven types of staff who have filled out the survey: editor (40), librarian (11), publishing representative (9), society/association representative (9), administration/management (6), director of the publishing house (1), and SP representative (1) (

Table 1. IPSPs’ and respondents’ profiles.

IPSP Profile		Respondent Profile
university/faculty	21	editor (editor-in-chief, editor, technical editor, associate editor)	40
learned society	18	librarian	11
research institute	6	IP publishing representative (president of the publishing committee, head of the publishing service)	9
library	3	society representative (president, treasurer, chairman)	9
museum	3	administration/management (professors, deans, vice-deans, assistant directors)	6
single journal	22	director of the publishing house	1
national publishing platform	1	SP representative	1
publishing house	1
library repository	1
error (personal web page)	1
Total	77	Total	77

).

The survey revealed that Croatian IPSPs predominantly operate under public entities, such as universities and research institutes (66%), while 25% are private, non-profit organisations (

Table 2. IPSPs’ or parent organisations’ type of legal entity.

Parent Organisation’s Type	# of IPSPs
Public organisation (e.g., university, research institute, laboratory, research organisation)	51
Private, not-for-profit organisation (e.g., charity, foundation, learned society, or association)	19
Other (please describe)	5
Company (owned by directors; limited liability)	1
Don’t know	1
Total	77

). Five respondents chose the ‘other’ category, including two non-governmental organisations, two professional societies, and one ‘society of associations’ (‘savez udruga’ in Croatian). The one respondent who self-identified as a company (a small one, in a category of 2–5 employees and publishing 2–5 journals and up to 50 books and conference outputs a year) is a service provider to institutional publishing.

The governance model of IPSPs is primarily based on a governing board, with 44 out of 65 respondents reporting their use. In contrast, management offices and external audits are less common, cited by 22 out of 56 and 16 out of 57 respondents. Other governance structures include publishing committees, councils, teams for digital collections management, offices, editors-in-chief, editorial boards, and faculty management. Formal documentation of IPSP activities is predominantly in the form of statutes, by-laws, and articles of association, while external legislation, requirements, and policies are less frequently referenced. One respondent identified a university senate decision as the primary formal document.

To promote collaboration and enhance institutional publishing quality, it is crucial for Croatian IPSPs to participate in professional circles and join relevant associations and initiatives. One-third of surveyed IPSPs are members of the Croatian Association of Scholarly Communication (CROASC/ZNAK). The European Association of Science Editors (EASE) is well-represented in Croatia, supported by an active regional chapter. While many IPSPs adhere to the guidelines of the Committee on Publication Ethics (COPE) (COPE, n.d.), only a small fraction hold formal COPE membership. None of the respondent IPSPs are affiliated with the Coalition for Advancing Research Assessment (CoARA), and only a few have endorsed the Helsinki Initiative on Multilingualism in Scholarly Communication or the TOP Guidelines.

3.2. Funding and Staff

Over half of the respondents (42 out of 77) reported starting each year with the approved budget. A survey revealed that excluding one IPSP with an annual budget exceeding EUR 1 million (a government-funded national publishing house), the average annual budget for IPSPs, based on data from 31 respondents who disclosed their budgets, is approximately EUR 30,000, with many operating on less than EUR 10,000 (

Table 3. IPSPs’ annual budgets.

Annual Budget (in Thousands of EUR)	# of IPSPs
<1	2
1–10	9
11–50	13
51–100	7
101–500	0
501–1000	0
>1000	1
Do not wish to disclose	2
Don’t know	8
Total	42

).

IPSPs closely monitor their expenses, with 61 out of 77 respondents indicating active oversight, particularly when receiving government subsidies. They are also required to submit annual financial reports. Parent organisations frequently provide in-kind support, such as facilities (69%), IT services (63%), and staff salaries (51%) (

Table 4. In-kind support from the parent institution.

Does Your Parent Organisation Provide the IPSP with In-Kind Support, Either in the Form of Labour, Facility Costs or Other (Excluding Peer Review)?
In-Kind Support Type	# of IPSPs
Facilities and premises	24
Service-specific IT services	22
General IT services (email, hardware, etc.)	19
Salaries of permanent staff	18
Salaries of temporary staff	6
Other (please specify)	3
N/A	4
Don’t know	1
HR management, general financial and legal services	0
Total	42

). However, support for human resource management, financial services, and legal services is typically absent. Notably, one respondent in the “Other” category stated, “All of the above in-kind contributions are provided not by our parent organisation but by the IPSP itself”.

The survey question concerning paid staff revealed that IPSPs are significantly supported by voluntary efforts, with 54% indicating an absence of paid staff. Among the rest, 26% have a staff of 2–5, 14% have less than two, and less than 6% have a staff of 6–10 or more than 30 employed or contracted staff involved in publishing (

Table 5. IPSPs’ paid staff.

How Many Paid Staff Are Directly Employed or Contracted by the IPSP (i.e., Editorial, Production and Operational Staff in Full-Time Equivalent (FTE))?
Staff Directly Employed or Contracted by the IPSP	# of IPSPs
None	41
Less than two	11
2–5	20
6–10	2
More than 30	2
Total	76

).

3.3. Services, Publications, and Publication Language

Publishing relies on a wide array of services, including editorial, production, IT, communication, administrative, legal, financial services, and training (

Table 6. Types of external services in terms of funding requirements.

	Voluntary Work	In-Kind Contributions	Outsourced	None/Not Applicable	Don’t Know
Editorial services	24	16	6	16	0
Production services	9	15	35	7	0
IT services	10	17	26	11	2
Communication services	14	14	4	22	3
Administrative, legal and financial services	3	16	12	21	3
Training, support and/or advice on publishing policies and best practice	16	13	4	21	4
Other	0	1	2	4	1

Total number of IPSPs using external services: 61. Multiple answers were allowed.

). Editorial services, such as manuscript processing, are typically provided voluntarily or as in-kind contributions, whereas production and IT services are predominantly outsourced. Communication, administrative, legal, financial services, and training are less commonly used and were frequently marked as “None/N/A” in the survey. Additionally, some IPSPs outsource specific services, such as printing, CrossRef DOI registration, and translations, which were categorised under “Other”.

Croatian IPSPs mainly publish academic journals, books, and conference outputs. Many also publish media and digital products and professional journals. On average, an IPSP publishes 1–5 scholarly journals, 11–100 scholarly articles per year, 1–10 academic books, and 1–20 conference proceedings (

Table 7. Number of publications by type.

Which of the Following Does the IPSP Publish or Provide a Service for?
Scholarly Journals in 2022	# of IPSPs	Academic Books in 2022	# of IPSPs
1	28	1–10	36
2–5	31	11–20	9
6–10	7	21–50	3
11–20	3	51–100	0
21–50	1	>100	0
51–100	0
>100	1
Scholarly Articles in 2022	# of IPSPs	Conference Outputs in 2022	# of IPSPs
1–10	6	1–20	39
11–50	40	21–50	7
51–100	10	51–100	4
101–200	7	101–200	1
201–500	3	>500	0
>500	2

). Although IPSPs predominantly come from the social sciences and humanities (21 and 19, respectively, out of 43) and have a multidisciplinary approach (24 out of 43), they are also represented across various disciplines (natural sciences: 16; engineering and technology: 11; medical and health sciences: 10), with a smaller presence in agricultural sciences (7 out of 43). Three respondents selected “non-academic” as a discipline.

Croatian IPSPs publish 5.3 journals, 75 articles, 9.2 books, and 21.8 conference outputs annually.

Among the surveyed IPSPs, only three exclusively publish content in Croatian, while an additional 37 predominantly publish in Croatian and also venture into other languages (the number of IPSPs that publish in Croatian, English, and another language is indicated with a plus sign and a specific language in

Table 8. Publication languages.

Language	# of IPSPs
Croatian	3
English	11
Croatian—English	26
+German	25
+Serbian	9
+French	8
+Slovenian	8
+Italian	11
+Russian	4
+Bosnian	3
+Spanish	2
+Hungarian	2
+Czech	1
One language	14
Two languages	26
Three languages	5
Four languages	3
Five languages	21

).

Respondents were prompted to rank languages by their prevalence, underscoring that Croatian is the primary publication language for 59% of responding IPSPs (Table 8). Conversely, 11 IPSPs exclusively publish in English. This indicates that 14 IPSPs confine their publications to Croatian or English, while 55 surveyed IPSPs are committed to multilingual publishing.

3.4. Open Science Practices

The DIAMAS survey addressed several aspects of open science practices, like the sharing of OA publications, OA/OS policies, copyright and licensing, open peer review, research data sharing and data availability policies, and new approaches towards research assessment. Some questions used a sliding scale ranging from 0 to 100, which some respondents misinterpreted.

Responses related to open science practices among Croatian IPSPs revealed that nearly all journals and a significant number of books and conference proceedings are published in open access (OA). Most IPSPs have institutional repositories for archiving and publishing OA content. Of 59 respondents to this question, 49 indicated 100% OA for journals, and nine IPSPs claimed 100% OA for books.

Croatia has a history of OA publishing since the 1990s but lacks a comprehensive national open access/open science (OA/OS) policy. Nevertheless, support exists through national laws, such as mandates for journals to be OA on the HRČAK portal for government subsidies. Furthermore, many IPSP parent institutions have OA/OS policies. Despite no formal national policy, the integration of OA principles within the scholarly domain remains strong. IPSPs’ OA/OS policies mainly address copyright, self-archiving, and open licences (

Table 9. The issues addressed by the open science/open access policy.

Does the IPSP’s Open Science/Open Access Policy Address the Following Issues?
Open Science/Open Access Policy Issues Addressed	# of IPSPs	%
Copyright	56	86
Self-archiving	41	63
Use of open licences	29	45
Use of identifiers	24	37
Metadata rights	17	26
Third-party copyright	9	14
Embargoes	7	11
Publication of negative research results	3	5
Other	4	6
Don’t know	6	9

Other (please specify): “This journal provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge. The journal content is published under the Creative Commons CC-BY-SA licence that allows others to share the work with an acknowledgement of the work’s authorship and initial publication in this journal”; “The policies of the national platform HRČAK”. Total number of respondents: 65.

). Most IPSPs use Creative Commons licences for all journals, or at least for some. We can observe that 16 IPSPs reported using CC licences for books despite the immaturity of the OA book landscape. Among Creative Commons licenses, CC BY, CC BY-NC-ND, and CC BY-NC are often used, with some IPSPs using multiple licenses.

Croatian IPSPs encourage authors to share published content through academic networks like ResearchGate. Allowing self-archiving in repositories is also common, and the embargo is imposed only by a few respondents. However, many IPSPs are not accepting submissions shared as preprints (

Table 10. OA/OS principles adopted by IPSPs.

Please Consider the Following Statements and Mark Those That Are Implemented at IPSP Level
	Yes, for Books	Yes, for All Journals	Yes, for Some Journals	No	I Don’t Know	N/A
Use Creative Commons (or other open licences)	16	44	10	5	4	6
Make references openly available according to the principles of I4OC (Initiative for Open Citations)	11	32	4	12	13	7
Allow self-archiving of your published content in open repositories (subject-specific or institutional)	17	49	4	4	5	7
Impose embargo periods for self-archiving	3	2	1	38	11	12
Accept submissions that have been publicly shared as a preprint or working paper before or on submission	6	14	9	24	12	7
Encourage or allow sharing the full text of your published content via academic sharing services (such as Academia.edu or ResearchGate)	12	49	4	4	5	8

Total number of respondents: 75.

). Many respondents are unaware of their policies regarding specific statements, as indicated by the substantial number of participants who selected “I Don’t Know” or “N/A.”

Thirty-two IPSPs reported having references openly available per I4OC principles, though this should be verified cautiously. A notable share of respondents was unsure about I4OC compliance, embargoes, and preprint acceptance.

Regarding open peer review, most responses were “No, (we are not enabling any form of open peer review)”. Still, ten IPSPs reported on already implemented open peer review, two are experimenting with it, and seventeen plan to implement it later.

Research data sharing is still developing, with most IPSPs needing corresponding policies. Despite the prevalence of negative responses (23 out of 75), we recorded 13 out of 75 cases of inclusion of data sharing in OS/OA policies, 20 out of 75 IPSPs implementing research data sharing at the journal level, and 4 at the publisher level.

The contributorship model, distinguishing between contributor roles, is not widely implemented, with many respondents unaware of it. According to the responses, only 12 IPSPs distinguished between contributor roles in their publications, while 28 responded negatively. As many as 24 IPSPs marked “Don’t know”, which could indicate their lack of knowledge about the contributorship model.

3.5. Editorial Quality, Editorial Management, and Research Integrity

The survey results revealed the significant involvement of Croatian IPSPs in the editorial management of their publications, which is also true for the whole DIAMAS sample, with around 70% of IPSPs saying they participate in the editorial management of publications (Armengou et al., 2023). Expectedly, IPSPs are involved mainly in recruiting and managing the editorial board members. According to the responses, they are also significantly involved in other tasks like sourcing reviewers, coordinating the peer review process, performing basic checks, and doing plagiarism scans. Only a few IPSPs have no tasks in editorial management. Similarly, a substantial number of IPSPs are engaged in managing editorial quality. Among them, over half of IPSPs create guidelines and instructions, define quality criteria and ensure compliance.

Croatian IPSPs predominantly employ double-anonymised peer reviews with anonymous authors and reviewers. Single-anonymised peer review, where authors do not know who the reviewers are but the reviewer knows the author’s identity, is used less. Some IPSPs indicate they practice open peer review, with few implementing open identities and one using open review reports. Eight IPSPs use editorial reviews.

More than half of the surveyed IPSPs have a policy on research integrity or publication ethics, slightly less than the whole DIAMAS sample, with around 63% of IPSPs having these policies in place. Still, 27 do not have such a policy, and some IPSPs are unaware of its existence.

3.6. Technical Service Efficiency

Responses regarding technical services provided by Croatian IPSPs indicate that most offer a full editorial workflow (55%), hosting (45%), and end-user interface (41%). Metadata and quality control (33%), software (27%), and partial editorial workflow (25%) are less common (

Table 11. Technical services provided by IPSP.

What Technical Services Does the IPSP Provide?
Technical Services	# of IPSPs
Hosting	34
Software	20
Full editorial workflow	41
Partial editorial workflow	19
Metadata and quality control	25
End-user interface	31
Other (Please specify)	3

Other: “Hrčak”, “web page”, “does not provide”. Total number of respondents: 75.

).

Technical services are primarily maintained in-house by dedicated publishing departments (25 out of 30 respondents) and IT departments or personnel (21 out of 35). The technical infrastructure is managed in-house by IT departments (24 out of 35), while some services are partially, mainly, or fully outsourced (8, 13, and 1 respondent(s), respectively, out of 20).

The predominant publishing system used to support editorial workflows in Croatia is the Open Journal System (OJS), followed by customised or self-developed open-source solutions. Other systems include Open Monograph Press (OMP) and WordPress, while commercial software options, such as Editorial Manager, Scholar One, Indigo, and Manuscript Manager, were rarely mentioned.

Persistent Identifiers (PIDs) are assigned by the majority of IPSPs (57 out of 75). The most commonly implemented PIDs include CrossRef-DOI, ISSN, and ISBN.

Standard international publishing practices include releasing metadata in a standardised format under an open license or Public Domain Dedication. Among Croatian IPSPs, 36% share metadata under CC BY or another Creative Commons license (

Table 12. Sharing metadata.

Does the IPSP Release Its Metadata Openly with a Standard Metadata Description Schema (MARC, MODS, DC, ONIX, JATS, TEI)?
Sharing Metadata Status	# of IPSPs
Yes, under Creative Commons Public Domain Dedication (CC0)	4
Yes, under CC BY or another Creative Commons licence	27
No	20
Don’t know	19
Other (please specify)	4

). However, many do not release metadata this way (27%), and a significant portion (25%) are still determining. Other (please specify) (Table 12) answers were as follows: “Yes, but not under a public license”; “Yes, but without the licence”; “Just starting with JATS XML for the journal”; and “Yes, UNIMARC”.

Regarding content formats, PDF is the prevalent format (99%), likely due to current international publishing practices, HRČAK’s previous lack of support for other formats and the ongoing presence of printed publications.

Almost two-thirds of respondents have archiving and backup policies in place, and 73% actively preserve published content through the Croatian National and University Library, the national infrastructure provided by the University of Zagreb, the University Computing Centre (SRCE), and institutional libraries or infrastructures.

The main technical challenges faced by Croatian IPSPs in providing adequate infrastructure and services include financial constraints (48 out of 67 respondents) and a lack of human resources (33 out of 67). The shortage of personnel also impacts key areas such as metadata quality (33 out of 67), interoperability (28 out of 67), and preservation (24 out of 67). Additionally, technical limitations in the existing infrastructure present challenges across all technical services.

While a lack of expertise is another significant issue, it appears to be evenly distributed across technical services and is less frequently addressed. Similarly, administrative constraints remain a less prominent focus in addressing these challenges.

3.7. Visibility, Communication, Marketing, and Impact

More than half of Croatian IPSPs prioritise better indexing. Beyond Web of Science Core Collection and Scopus, they seek indexing in Directory of Open Access Journals (DOAJ), Directory of Open Access Books (DOAB), ERIH PLUS, PubMed, Google Scholar, Google Books, and Open Access Publishing in European Networks (OAPEN). Almost half of IPSPs are satisfied with their current indexing status. Still, the main challenge for Croatian IPSPs in achieving better indexing is meeting the technical participation criteria. Non-technical criteria, metadata requirements, membership fees, and recurring charges pose significant challenges.

Publicly displaying metrics is less common, with fewer than half of IPSPs doing so (31 out of 75). The prevalent metrics include data about submissions, acceptance, and publication dates (27 out of 31); article-level usage metrics, like visits, views, and downloads (18 out of 31); publication-level usage metrics, such as Journal Impact Factor (17 out of 31); and publication-level usage metrics, such as visits, views, and downloads (12 out of 31) (

Table 13. Publicly displayed metrics.

Type of Metrics	# of IPSPs
Submission, acceptance, and publication dates	27
Article-level usage metrics, such as visits, views, and downloads	18
Publication-level usage metrics, such as visits, views, and downloads	12
Article-level impact metrics, such as citation counts	9
Publication-level impact metrics, such as Journal Impact Factors	17
Rejection rates	3
Altmetrics, such as Altmetric and Plum X Metrics	2
Dimensions citation badges	0
Widget showing geographical spread of visitors	1

Other (please specify): “This differs depending on the type of publication (it is not the same for the articles and for the journals, not even for all journals)”.

). It is expected that IPSPs are more aware of the article- and publication-level metrics provided for their journals by the national HRČAK platform. Citation badges provided by Dimensions are not known to IPSPs, and the widget showing geographical spread of visitors is used only by one IPSP.

Regarding communication, many IPSPs maintain a newsletter, social media, or networking profile (43 out of 75) to keep their community informed.

4. Discussion

The results highlight the strengths and weaknesses of Croatian institutional publishers in advancing the diamond open access model. It should be noted that the significant representation of journals and journal editors in the survey could weaken the representation of other types of publications issued by IPSPs, resulting in skewed results towards journals’ practices.

RQ1: What types of institutions and governance models are predominant among Croatian institutional publishers? Are they present in local and international professional circles?

Croatian IPSPs predominantly operate under public entities, such as universities and research institutes, and private, non-profit organisations, such as learned societies. These findings are consistent with the whole DIAMAS sample, where two-thirds of IPSPs are public organisations (such as most universities), and together with private but not-for-profit organisations (such as most societies and associations), over 85% of responding IPSPs are indeed not for profit (Armengou et al., 2023). Governance structures are varied, with many IPSPs employing governing boards, but formalised management practices remain limited.

The national professional circle of Croatian IPSPs is strong, largely due to the active efforts of the Croatian Association for Scholarly Communication (CROASC/ZNAK), which plays a pivotal role in major activities related to promoting and implementing open science principles. Croatian publishers and editors also benefit from their connection through the HRČAK platform.

In contrast, international engagement is significantly weaker and Croatian IPSPs rarely participate in major initiatives, learned societies, or professional networks. For instance, while many Croatian IPSPs follow the COPE guidelines to promote research and publication integrity, formal COPE membership is almost non-existent. Similarly, the CoARA, which aims to reform research assessment systems, is particularly relevant for small diamond publishers but sees no involvement from Croatian IPSPs. Some respondents were uncertain about their institution’s membership status, indicating a need for increased awareness and transparency. An exception is the Croatian EASE Regional Chapter, a valuable link between Croatian IPSPs and the broader international publishing community, providing an avenue for greater global integration and collaboration.

RQ2: What are the primary funding sources for Croatian institutional publishers, and how many staff members are employed?

The dominance of public entities reflects a non-profit approach aligned with diamond open access principles. The Croatian government is the primary funder, with national ministries being the leading contributors, followed by counties, national foundations, cities, universities, private companies, and state agencies. However, a firm reliance on government subsidies, in-kind contributions from parent institutions, and volunteer work poses significant challenges and risks to sustainability (Yoon et al., 2024; Dufour et al., 2023). The results revealed that despite this reliance on government subsidies and institutional support, many IPSPs start the year without an approved budget. Croatian IPSPs are primarily driven by voluntary efforts, with over half indicating no paid staff. Stable funding mechanisms, such as multi-year grants, could alleviate financial uncertainty.

Survey responses to open-ended questions highlight several key challenges in funding, which we categorised accordingly:

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Continuity: Ensuring permanent, stable income is crucial for uninterrupted publication and development;

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Regularity: Delays in funding from ministries complicate financial planning;

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Sufficiency: Many IPSPs report insufficient state support and seek increased funding for essential services and development;

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Unexpected Changes: Sudden changes in public financing systems pose risks.

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Financial Literacy: Improved knowledge and skills in financial sustainability are needed;

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High Costs: Rising costs for copy-editing, printing, and online submission systems are a concern;

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Printing: Balancing the costs of print editions with the need for visibility in open access is challenging;

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Voluntary Work: Reliance on unpaid labour makes it difficult to retain skilled personnel;

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Dependency on Parent Institutions: Additional stable funding sources are necessary for further development.

Interestingly, according to the collected data, most respondents consider fixed and permanent subsidies from the parent organisations and permanent public and government funding stable or very stable. Delays and remittances did not influence the perception of the reliability of government funds. In contrast, IPSPs consider voluntary contributions, content and print sales, and article processing charges highly unstable.

During the past decades, Croatian journals were funded mainly by the Ministry of Science and Education as the main funder and the Ministry of Culture. Recently, the Ministry of Science and Education changed its subsidy policy and started distributing the finances for scholarly publications through programme agreements with public universities and research institutes as a part of institutional subsidy for research infrastructure. Although we can consider such an approach positive for several reasons (institutions’ support for their own scientific publishing can result in better communication and improvement of funding criteria, encouraging an increase in quality), it remains to be seen how it will reflect on the development of diamond scientific publishing in Croatia.

According to the survey results, IPSPs consider the changes in modalities for government funding without timely announcements and public consultations a severe challenge. They also face an increase in the price of printing, copy-editing, and securing an appropriate online submission system. Even though print sales are very unstable, most Croatian IPSPs still print their journals. The possible reasons for this could be the unclear wording in one of the Ministry’s funding criteria and the vague reluctance of IPSPs to switch to an exclusively online version.

The survey question concerning paid staff revealed that IPSPs are significantly supported by voluntary efforts, with over half indicating an absence of paid staff, compared to the whole DIAMAS sample, where only around one-quarter of IPSPs reported having no paid staff. When talking about different regions from the DIAMAS survey, Croatian results are mostly comparable to those from the Southern Europe region (Armengou et al., 2023).

RQ3: What range of services, types of publications, and languages do Croatian institutional publishers provide?

The distinction between in-house services used for IPSP publishing activities, services provided by IPSPs to other publishing organisations (within or outside their parent institution), and external services from third-party providers proved to be more complex than anticipated in the survey. Respondents faced challenges in categorising the type of services they use or offer, reflecting academic institutions’ intricate and multi-layered organisational structures, where publishing activities are often distributed across various levels (Armengou et al., 2023). Despite these complexities, the collected data provide valuable insights into the range of services utilised and offered by IPSPs.

IPSPs also provide in-house services for editors, authors, reviewers, and readers. IPSPs primarily offer editorial services, including manuscript selection and peer review. They also provide production services like copy-editing, proofreading, typesetting, and metadata management. About half offer IT services, including submission systems and websites; communication services like marketing and dissemination; and administrative, legal, and financial services. Some IPSPs offer training, support, or counsel on publishing policies and best practices. Compared to the whole DIAMAS sample, the services Croatian IPSPs provide are comparable, except for the training, support, and/or advice services, which are provided considerably less often (Armengou et al., 2023).

External services often rely on nationally or internationally provided infrastructure like HRČAK or the national DOI Office at the Croatian National and University Library. Editorial services, including manuscript selection and peer review, are typically provided voluntarily or as in-kind contributions, while production and IT services are mostly outsourced.

The publication language practices among surveyed IPSPs in Croatia reveal a diverse multilingual landscape. While some IPSPs exclusively focus on publishing content in Croatian or English, most engage in multilingual publishing efforts. Over half of respondents disseminate content in multiple languages, with many providing bilingual or sequential versions across various documents or journals.

Multilingualism extends to abstracts, with many IPSPs offering abstracts in different languages, predominantly translating them into English if the source language differs. Moreover, several IPSPs extend translation services to metadata and language-check assistance for authors, showcasing a dedication to inclusive and accessible communication.

The Croatian language is among numerous languages spoken by small national groups, considered low-resource languages with a lack of training data (Begoli et al., 2024), causing a slower advancement of machine translation tools. Therefore, a reliance on human translators persists, highlighting additional costs for IPSPs. Although emerging tools offer potential, IPSPs still predominantly support a limited number of languages, underscoring the need for continued exploration and adaptation to technological advancements.

RQ4: To what extent do Croatian institutional publishers implement open science practices?

The survey results reveal a strong foundation for open science practices among Croatian IPSPs, particularly related to open access publishing. Croatian IPSPs demonstrate a well-established tradition of OA publishing, with nearly all journals and a notable proportion of books and conference proceedings available in OA. This aligns with Croatia’s history of OA initiatives dating back to the 1990s, despite the absence of a comprehensive national OA/OS policy. The reliance on the HRČAK platform and institutional OA/OS policies has supported the widespread adoption of OA practices, further incentivised by government subsidies contingent on OA compliance. However, while OA for journals is nearly universal in Croatia, the OA book landscape is still underdeveloped, as reflected in the small share of OA books and modest use of Creative Commons (CC) licenses.

Most IPSPs have adopted OA/OS policies addressing copyright, self-archiving, and open licensing. However, compared to the whole DIAMAS sample, the use of open licences is addressed in fewer instances in the open science/open access policies of Croatian IPSPs (Armengou et al., 2023). In addition, less than half of the IPSPs address critical issues such as metadata rights, use of persistent identifiers, or third-party copyright.

The survey indicates that open peer review remains largely unexplored, with only a few IPSPs reporting implementation or plans to adopt it. This finding is consistent with the broader challenges of integrating transparency into peer review systems. Similarly, preprint sharing is not yet widely adopted, with many IPSPs explicitly not accepting submissions shared as preprints.

Research data sharing is still in its infancy among Croatian IPSPs. While a few respondents reported data-sharing policies at the journal or publisher level, most lacked such frameworks. This gap reflects broader challenges in aligning Croatian IPSPs with global open science initiatives emphasising data availability and reproducibility.

The contributorship model, which provides a more nuanced distinction of contributor roles supporting new ways of research assessment, has not been widely adopted. The high number of uncertain responses suggests limited awareness of this model.

While Croatian IPSPs are active in OA publishing, with a strong tradition and institutional support, there are gaps in understanding and implementing broader OS practices, especially in preprint sharing, open peer review, and the contributorship model. Increased training and capacity building could enhance these practices.

RQ5: How do Croatian institutional publishers ensure and manage editorial quality and research integrity?

The survey results underscore the active role of Croatian IPSPs in editorial management and quality assurance, reflecting trends observed across the DIAMAS sample. While the involvement of IPSPs in tasks such as recruiting and managing editorial board members is expected, without an insight into the structure of the respondents (mainly editors), tasks such as sourcing reviewers, coordinating the peer review process, performing basic editorial checks, and conducting plagiarism scans would undoubtedly surprise us.

Double-anonymised peer review is the predominant peer review method, ensuring anonymity for both authors and reviewers. Single-anonymised peer review is less commonly employed, and while some IPSPs are experimenting with open peer review practices, its adoption remains limited. This aligns with broader hesitancy to embrace more transparent peer review processes, which may require additional training and infrastructure support.

Over half of the surveyed IPSPs have established guidelines and instructions, quality criteria, and mechanisms for compliance to manage editorial quality effectively. However, the adoption of research integrity and publication ethics policies, while present in the majority, leaves room for improvement.

The relationship between publishers and editors is essential and should be clearly defined, adhering to ethical norms in scientific publishing. Publishers should handle recruiting and managing editorial board members, providing financial support, space, equipment, necessary tools, and training to ensure quality and independent editorial work. Editors, on the other hand, should manage the content, including the peer review process.

RQ6: What technical services do Croatian institutional publishers provide, and what are the main challenges?

Croatian IPSPs offer a range of technical services primarily maintained in-house, with publishing and IT departments managing most of the infrastructure. This internal management depicts a reliance on institutional resources rather than outsourcing, which is used only to a limited extent. The predominant use of the Open Journal System (OJS) as a publishing platform reinforces the role of open-source solutions in supporting editorial workflows from submission to publication (Dufour et al., 2023). Other open-source tools, such as Open Monograph Press (OMP), further demonstrate a preference for adaptable and cost-effective systems, although some IPSPs employ commercial software. The central installations of OJS and OMP maintained by SRCE, which are freely available to all Croatian IPSPs, undoubtedly enhance the popularity and usage of open-source tools.

Persistent Identifiers (PIDs) are widespread among Croatian IPSPs, with most of them assigning PIDs to their publications. However, the adoption of standardised metadata practices is uneven. While 36% of IPSPs release metadata under Creative Commons licenses, 27% do not share metadata openly, and 25% are uncertain about their metadata policies. Although its policy resembles the CC BY license, the national platform HRČAK has not clearly defined its metadata terms under a Creative Commons license or Public Domain Dedication. Clarifying HRČAK’s metadata policy would benefit other IPSPs. The open comments suggest that some IPSPs are in the early stages of adopting standardised metadata schemas.

Currently, the assignment of Persistent Identifiers (PIDs) in Croatia is relatively complex and could be easily improved. While a national Digital Object Identifier (DOI) office within the National and University Library only serves journal publications and assigns DOIs solely to original scientific articles, publishers needing DOIs for other types of content must seek individual memberships in CrossRef (for publications) or Datacite (for datasets). Although using CrossRef DOI is common among Croatian IPSPs, not all IPSPs assign PIDs to all published content. Given the importance of DOIs for enhancing discoverability, this area needs attention.

PDF remains the dominant content format. Compared to Croatia, the whole DIAMAS sample uses other formats more, with 41% of IPSPs using HTML to display content and another 20% using the XML format (Armengou et al., 2023). Efforts made by Croatian IPSPs to adopt HTML and XML formats are underway, and their representation should be increased.

Most IPSPs have archiving and backup policies and actively preserve published content using national infrastructure, such as the Croatian National and University Library and the University Computing Centre (SRCE).

Financial constraints and lacking human resources are the most pressing challenges for Croatian IPSPs. These limitations impact critical areas such as metadata quality, interoperability, and long-term preservation. Additionally, technical limitations in existing infrastructure create barriers across all technical services, underscoring the need for infrastructure upgrades. While a lack of expertise is also a challenge, it appears less frequently addressed than financial and staffing issues.

RQ7: What strategies do Croatian institutional publishers use to enhance the visibility and impact of their publications?

Indexing in prestigious databases and directories, such as Web of Science Core Collection, Scopus, DOAJ, and ERIH PLUS, remains a top priority for over half of Croatian IPSPs. However, technical participation criteria, including metadata requirements and compliance, emerge as the most significant barriers to achieving broader indexing. Non-technical factors, such as membership fees and recurring charges, further complicate the process.

Publicly displaying metrics is not yet widespread, with fewer than half of the IPSPs providing such data. Among those that do, the most common metrics are operational statistics (e.g., submission, acceptance, and publication dates), followed by article-level usage metrics (e.g., visits, views, and downloads) and publication-level impact metrics (e.g., Journal Impact Factor). However, advanced metrics such as citation counts, altmetrics (e.g., Altmetric or PlumX), and tools like Dimensions citation badges remain largely unexplored.

This lack of adoption could indicate limited awareness or resource constraints. For example, while HRČAK provides article- and publication-level usage metrics (e.g., visits and downloads) for all journals, not all IPSPs leverage these data effectively. Additionally, the geographic visitor widget is used by only one respondent, suggesting unused potential in showcasing the reach and impact of publications.

In terms of communication strategies, many IPSPs actively maintain newsletters, social media profiles, or other networking tools to engage with their communities. With many respondents using these platforms, it is evident that digital communication is a key strategy for IPSPs to increase visibility and foster connections with stakeholders. Further leveraging these tools for targeted marketing and dissemination could enhance the reach and impact of their publications.

5. Conclusions

This study underscores the pivotal role of Croatian institutional publishers and service providers (IPSPs) in advancing diamond open access publishing and promoting equitable scholarly communication. Strengths include a strong tradition of diamond OA journal publishing, reliance on public funding, and commitment to multilingualism, supported by platforms like HRČAK and open-source systems for editorial management such as OJS.

Croatian IPSPs mainly operate under community-owned public or non-profit entities and rely heavily on voluntary work, with many lacking paid staff. Financial and human resource constraints challenge their ability to meet all technical requirements, improve metadata quality, and adopt more advanced open science practices. While OA journal publishing is widespread, OA books remain underdeveloped.

Editorial quality is supported by guidelines and peer review processes, with double-anonymised peer review prevailing. However, open peer review and contributorship models are underexplored. Research data-sharing policies are limited, reflecting broader gaps in aligning with global OS standards.

Technical infrastructure, predominantly managed in-house, relies on open-source solutions, with PIDs and archiving policies being common. However, existing infrastructure requires upgrades to address interoperability and preservation challenges. Indexing in major databases like Scopus and Web of Science Core Collection remains a priority, but IPSPs face barriers such as compliance with metadata standards. Metrics tracking is limited, with advanced tools like citation counts and altmetrics rarely employed.

To ensure sustainability, national open science policies, sufficient funding, and infrastructure upgrades are essential. International collaborations, training programs, and technical support can resolve some skill gaps and elevate Croatian IPSPs’ global visibility. Strengthening capacity for OA books, improving editorial workflows, and advancing research integrity policies will further position Croatian IPSPs as leaders in equitable and accessible knowledge dissemination.