Objectives: A systematic analysis of organ donation–related publications can enable assessment of the existing knowledge base and can help inform future policy development Here, we analyzed scientific publications addressing public awareness on organ donation and transplantation between 2000 and 2025 by bibliometric method. Materials and Method: We conducted a descriptive study based on bibliometric analysis. We obtained data using EkşiVeri 1.0.5 R-Shiny Integrated Smart Data Analysis and Analytics Application. We obtained sources from an open access database known as (TR Index, a national database developed by TÜBİTAK ULAKBİM in accordance with international standards to provide researchers with access to national and scientific content in electronic environment). We searched publications using the key words “organ donation” and “transplantation.” We evaluated relationships between concepts using network metrics such as modularity, centrality and average path length.
Results: Data were obtained from 63 research articles published by Turkish authors. Word networks with 23 nodes and 54 links at the title level and 20 nodes and 59 links at the subject level were created. Analysis of the title word network showed that the terms organ, donation, and transplantation were positioned as thematic centers with high degree and betweenness centrality values. In addition, broader and interdisciplinary concepts such as “medicine,” “services,” “ethics,” and “policy” characterized the subject area. Publications often focused on students, health care professionals, and patient groups and revolved around themes of knowledge, attitudes, and behaviors.
Conclusions: Title searches for “organ” and “transplantation” showed publications originating from Türkiye that not only focused on organ donation and transplantation but also encompassed a broader and systemic context. Future studies should focus on different groups and increase initiatives aimed at raising public awareness of organ transplantation.

Key words : Literature search, Organ transplant awareness, Thematic analysis

Introduction
Organ donation is when a person, while alive and of their own free will, allows their tissues and organs to be used for the treatment of other patients after their medically determined death. Although organ donation plays a vital role in addressing life-threatening organ failures, donation remains at a level that meets only a small fraction of the need, both globally and in Türkiye.¹ In 2023, 173 848 organ transplants were performed worldwide, which still met less than 10% of the actual need.² Globally, approximately 26.6% of the 45 861 organ transplants performed in 2023 were from deceased donors.² This rate is 49.79% in the United States and around 30% in European countries. In Türkiye, only 7.9% of the 4586 organ transplants performed in 2024 were from deceased donors. Although Türkiye is well below the global average in terms of transplants from deceased donors, Türkiye ranks first in Europe in terms of transplants from living donors.³ The low average in Türkiye is because organ donations from deceased donors are insufficient. In a study that examined 27 146 organ transplants performed in Türkiye between January 2008 and December 2016, approval rates for organ donation by families of brain-dead male donors and brain-dead female donors were 30.5% and 26.9%, respectively.⁴ In another retrospective study that evaluated 12 years of data on patients diagnosed with brain death in Türkiye, families refused organ donation in 51.2% of cases, even when the deceased person’s signed consent for donation was clearly documented; religious concerns and distrust in the system were identified as the leading reasons for refusal.⁵ In a study from Uğur (2018) who used Eurobarometer 72.3 data, more than half of the 1004 participants from Türkiye reported that they did not want to donate their organs, only 19% were aware of the legal regulations related to organ donation, and the most commonly cited reason for not wanting to donate was religious grounds (35.7%).⁶ Although religious authorities in Türkiye have issued statements supporting organ donation, the ongoing debate surrounding brain death and its religious permissibility has not been fully clarified. In addition, investigations in Türkiye have shown that individuals generally lack adequate knowledge about organ transplantation.^6-8 As a result of this lack of knowledge and widespread misconceptions, Türkiye’s organ donation rates remain insufficient, placing an excessive burden on living donors within the transplant system.⁴ Moreover, system inefficiencies and logistical delays can lead to missed opportunities for transplantation. Therefore, scientific studies that aim to understand the factors influencing individuals’ attitudes and behaviors toward organ donation and to raise public awareness play a key role in increasing donation rates.^9,10 In this context, systematically analyzing organ donation-related publications can enable an assessment of the existing knowledge base and can help inform future policy development.¹¹ In this study, we aimed to identify gaps and trends in the literature on organ transplantation and to reveal its conceptual framework by conducting a bibliometric analysis of scientific publications.

Materials and Method

Study design
We conducted a bibliometric and text-mining-based science mapping study to describe the literature on organ transplantation and reveal its conceptual structure. Text-based analyses were performed using the EkşiVeri 1.0.5 (R-Shiny-based) application, which combines word cloud, word network, correlation-based related words, and artificial intelligence-supported thematic classification in a single platform for Turkish texts.¹²

Data source and dataset construction
We obtained bibliographic records from the open-access database known as TRDİZİN (TR Index), created by the National Academic Network and Information Center (ULAKBİM). TRDİZİN comprises 1784 journals in the core subjects of Natural Sciences and Social Sciences.¹³ In this study, we searched for Turkish research addresses by using the key words “organ donation” and “transplantation” covering the years 2000 through 2025. Inclusion criteria were that the study was a research article, that it had a Turkish address, that the publication language was Turkish or English, and that it was about organ transplantation. Exclusion criteria were that it was a review article. Suitable records were exported in Excel format and prepared for analysis. The prepared Excel file was uploaded to the EkşiVeri 1.0.5 interface and stored in the system memory. In the application’s data processing layer, we used data manipulation functions for efficient processing of large datasets and normalization specific to Turkish texts and applied extended stop-word management. In the analysis, title, abstract, key words, author, publication year, and publication language fields were analyzed as text sources.¹²

Results

Word cloud, word network, and matrix for the title
Examination of the title word cloud showed that the most frequently repeated words at the word level were organ (n = 47), donation (n = 40), and transplantation (n = 32), and the core of the dataset was the theme of “organ donation and transplantation.” In addition, the prominence of terms such as knowledge (n = 18) and attitudes (n = 16) showed that the publication titles focused on human factors in the knowledge-attitude axis in addition to medical processes. Words indicating the target group were also prominent in the titles; for example, the expressions students (n = 12), university (n = 11), and faculty (n = 5) indicated that a significant portion of the studies were conducted through university/student samples, whereas the term patient(s) (n = 11) showed that the clinical or patient population was also included (Figure 1). Analysis of the title keyword network showed that the network comprised 23 nodes and 54 edges. The average degree was 4.7 and network density was 0.2134, indicating a moderate level of connectivity among the key words appearing in titles. The average path length was calculated as 0.3, suggesting short paths between concepts. The modularity value (0.1595) indicated the absence of clearly delineated sub-thematic clusters in the title network and suggested that concepts were organized around a shared core (Figure 2). According to the centrality analysis, “organ” had the highest degree (degree = 17) and the highest betweenness centrality (betweenness = 102.17), identifying this term as the most central concept in the network. “Donation” (degree = 11; betweenness = 43.17) and “transplantation” (degree = 9; betweenness = 24.50) were the other dominant concepts in the title network. In addition, the relatively high centrality of “knowledge” (degree = 10) and “students” (degree = 10) indicated that themes related to knowledge levels and student-focused research featured prominently across a considerable subset of titles (Table 1).

Word cloud, word network, and matrix for the subject
In analysis of the subject word cloud and frequency, thematic concentration at the subject level clustered around the terms health (n = 49), transplantation (n = 42), medicine (n = 39), services (n = 38), and general (n = 31). This distribution indicated that the dataset encompassed not only clinical transplant practices but also broader classifications related to health services and systems and medicine. The appearance of concepts such as policies (n = 22) within the subject themes further suggested that the transplant/donation field extended into policy and regulatory dimensions (Figure 3). The subject key word network comprised 20 nodes and 59 links. The average degree was 5.9 and network density was 0.3105, indicating a high level of interconnectedness among subject key words. The average path length was 0.29, suggesting short paths between concepts and relatively close relationships across the network. The modularity value (0.2189) indicated that subject terms form some sub-clusters, although the network did not exhibit a fully fragmented structure (Figure 4). According to the centrality analysis, “health” had the highest degree (degree = 14), making it the most central concept in the network. “Transplantation” and “medicine” (both degree = 11) also emerged as key central nodes. “Medical” showed the highest betweenness centrality (betweenness = 64.50), highlighting its role as a strong bridging term connecting different subject clusters. In addition, “services” (degree = 10; betweenness = 29.33) and “policies” (degree = 8; betweenness = 22.00) indicated that health service delivery and policy dimensions are prominent within the subject network (Table 2).

Thematic analysis results
A total of 7 main themes were identified in the thematic analysis of the titles. The most dominant theme was organ donation and transplantation, accounting for most of the total frequency. The total frequency of the top 3 key words was 119, indicating that the titles were concentrated around these core concepts (Table 3). Seven main themes were also identified in the thematic analysis of the topics. The most dominant themes were health and medicine, organ transplantation, and health services and systems, with a total frequency of 130 for the top 3 key words (Table 4).

Discussion
This bibliometric analysis, including word clouds, word networks, and matrices at the heading and subject levels, as well as thematic analyses, provided a broad perspective on the conceptual structure of the organ donation and transplant literature. The findings revealed overlapping and reinforcing emphasis within the headings and subject categories. The word cloud visualized textual density based on word frequencies obtained from scientific publications on organ donation and transplantation, providing a visual summary of the most emphasized concepts in literature. The results of the title word cloud and frequency analysis clearly showed that the core of the literature was formed by the concepts of organ, donation, and transplantation. This indicated that studies in the field of organ donation and transplantation adopted a specific, direct, and goal-oriented discourse at the title level. Examination of the title word network and matrix revealed low modularity (0.1595) and short average path length (0.3), indicating that the titles were not distinctly subthemes and that the concepts were concentrated around a common core. In particular, the highest degree of intercalation centrality of the word “organ” revealed that this concept played a unifying and guiding role at the title level. High intercalation centrality in the literature indicated that a concept acts as a bridge between different themes and forms the conceptual backbone of the field.¹² Another notable finding in the title analysis was the high frequency and centrality of human-factor terms such as knowledge, attitudes, opinions, and behaviors. This pattern indicated that knowledge, attitudes, and behavioral determinants constituted a major research focus in the organ donation literature at the title level. The prominence of terms such as students and university further suggested that a substantial proportion of studies concentrated on student populations and academic settings. This finding was consistent with prior research emphasizing the critical role of education in strengthening organ donation-related behaviors.^6-8,15 At the subject level, the word cloud and thematic analyses revealed a broader and more system-oriented structure. The high frequencies of terms such as health, medicine, services, and transplantation indicated that the studies were not limited to individual- or clinic-level perspectives; rather, they were also framed within the contexts of health systems, service delivery, and medical disciplines. The higher network density (0.3105) and modularity (0.2189) observed in the subject key word network further suggested that, compared with titles, subject categories exhibit greater thematic diversity and more pronounced sub-clustering. The fact that the word “medical” had the highest intercalation centrality in the subject network indicated that this concept functions as a connecting node between clinical, service, and policy themes. This trend revealed, as in the literature, that organ donation rates were closely related not only to individual factors but also to systemic and policy arrangements.^4,16 The representation of concepts such as ethics, public, environmental, and social at the subject level revealed that organ donation decisions were considered not only in medical but also in ethical, social, and cultural contexts. This finding was consistent with previous studies in our country that emphasized the central role of ethical and religious sensitivity, particularly in discussions of deceased donor organ donation and brain death.^6-8,17,18 The bibliometric findings obtained at the title and subject level in our study showed that the organ donation and transplant literature was structured on 2 complementary planes. Title analyses revealed that the studies were largely presented with a specific, focused, and direct discourse centered on organ donation and transplantation. Low modularity and short path length indicated that the titles were concentrated around a common conceptual core without branching into distinct subthemes. In contrast, subject analyses revealed that literature addressed concepts such as health, medicine, services, and policies more broadly. The higher density and modularity in the subject network suggested that health services, policy, ethics, and social dimensions were considered together.

Strengths and limitations
The strength of our study was showing the conceptual structure of the literature by examining publications in the field of organ donation and transplantation at the title and subject levels using multidimensional bibliometric methods. However, because analyses were limited to publications in the TR Index, the findings may not fully reflect international literature. Therefore, the results should be evaluated within the Turkish context.

Conclusions
This bibliometric analysis revealed that the literature on organ donation and transplantation exhibits a focused and homogeneous structure at the title level, while displaying a multidimensional and system-based structure at the subject level. Studies focused on individuals’ knowledge, attitudes, and behaviors, while also integrating with health care services, policy, and ethical dimensions. These findings highlight the importance of a holistic approach to strategies aimed at increasing organ donation; this approach should encompass individual awareness campaigns, institutional practices, and national policy regulations. Structured educational programs targeting health care professionals and students, who play a significant role in public education, are considered effective in fostering positive attitudes toward donation. Addressing the ethical and socio-cultural factors that are hindering increased organ donation through interdisciplinary and mixed-methods approaches will provide a more holistic solution to the problem.