Drivers of Influence in Top Transplant Journals: Predictors of Positive Impact

Introduction

Citations play a vital role in scientific publications by establishing durable connections to the referenced sources and attributing intellectual credit to the authors being cited (1,2). They serve as tangible evidence of an article's reach within the scientific community, reflecting its dissemination and impact (3,4). Furthermore, citations provide a quantitative measure of recognition, serving as a means for peers to evaluate the quality and significance of the cited work (4,5). Consequently, being cited holds substantial value for scientists, as it serves as a motivating factor and plays a pivotal role in the assessment and evaluation of their research contributions (6). In an effort to enhance their impact metrics, journals strive to improve their standing in the scientific community. Two widely recognized metrics, the Journal Impact Factor (JIF) developed by Clarivate®, and CiteScore developed by Elsevier®, are commonly used for this purpose (7,8,9,10). Both metrics use similar calculation methodology, with citation on nominator and number of publications on the denominator, meaning that the more the publications or the lower the citation, the negative impact of these impact metrics. Traditionally, the impact factor (IF) of a journal has been used as an indicator of the quality of a journal and an author’s scientific standing (11,12). Several factors have been found to be correlated with the JIF; these include the country’s income level and the language of publishing, as well as variables such as study sample size and the publication year (13). It is well known that articles published in top journals in each field receive higher citations, regardless of their topics (8,12,14). However, if an article published in such journals received citations less than the journal’s impact factor, such articles will have a negative impact on the journal’s impact factor, meaning that it resulted in lowering this impact metric. The aim of this study was to assess factors that predict a positive impact on articles published in the top five transplantation journals in their respective journals. This study distinguishes itself from prior bibliometric analyses related to transplantation, which mainly examined publication trends, citation patterns, or author productivity, by quantifying the influence of specific article-level factors, such as open access status, organizational affiliation, and authorship format, on each article’s contribution to its corresponding journal’s impact factor enabling a direct assessment of variables linked to a favorable or negative impact on JIF.

Materials and Methods

Results

A total of 2,461 article and review were published by the top solid organ transplantation journals in the years 2019 and 2020, majority were published by American Journal of Transplantation (841, 34.2%), followed by Transplantation (633, 25.7%), Nephrology Dialysis Transplantation (472, 19.2%), Liver Transplantation (276, 11.2%), then Journal of Heart and Lung Transplantation (239, 9.7%). Journals significantly differed in the percentage of articles that had positive impact (p< 0.001), with highest proportion for Transplantation (172, 27.2%), followed by Nephrology dialysis transplantation (108, 22.9%), American Journal of Transplantation (183, 21.8%), Journal of Heart and Lung Transplantation (32, 13.4%), then Liver transplantation (19, 6.9%). Figure (1) We performed univariate analysis to assess factors that are related to article’s positive or negative impact on JIF, supplementary table (1). Factors significant in the univariate analysis were tested in the logistic regression model supplementary table (2). On regression analysis, the model was significant at <0.001 with predictive accuracy of 79.1% and a Nagelkerke R2 of was 0.053. Significant predictors of positive JIF impact include: Number of authors (p= 0.006), associated with 1.3% (0.4% to 2.3%) increase in potential impact on JIF with increasing number of authors. • Open access publication (p< 0.001), associated with 61.9% (28.5% to 103.9%) increase in potential impact on JIF. • Affiliation with top five institutions (p= 0.014), associated with 53.8% (9% to 117%) increase in potential impact on JIF. Moreover, several topics were significantly predictive of JIP: • Kidney-related topics (p < 0.001) were associated with a 63.2% increase (32.1%–101.7%) in JIF impact. • Lung-related topics (p = 0.025) were associated with a 33.3% decrease (5%–53.1%) in JIF impact. COVID-19–related articles (p < 0.001) demonstrated a striking 1,449.8% increase (886.5%–2,371.1%) in JIF impact.

Discussion

In this study, we assessed the factors that contributed to either a positive impact (high citation counts) or a negative impact (low citation counts) of articles published in the top five solid organs transplantation journals. The analysis revealed significant differences in the proportion of articles with a positive impact across the transplantation journals. Notably, publications addressing COVID-19 exhibited the most substantial positive impact. Moreover, articles discussing kidney transplantation had a positive impact, while those discussing lung transplantation had a negative impact. This discrepancy could be attributed to the substantial effect of COVID-19 on organ transplantation, with kidney transplantation being the most affected among various specialties (15). Kidney is the first and most frequently transplanted organ (16) Additionally, the number of end stage kidney disease patients are growing exponentially (17). These factors contribute to the extensive discussions and research surrounding kidney transplantation compared to topics such as liver, lung, and heart transplantation (18). With regard to article authorship, articles with more authors or authors from top affiliations were generally more likely to have positive impact, which is consistent with previous studies that indicate a higher number of authors facilitate a wider range of expertise and a greater diversity of ideas and data types, particularly in interdisciplinary collaborations (19,20,21). Additionally, our study revealed that open-access articles had a higher chance of receiving citations and achieving a positive impact. This finding aligns with previous research conducted across a variety of disciplines including philosophy, political science, engineering, mathematics, physics, computer science and agriculture, which consistently demonstrated that open access publications exhibit greater research impact and citation rates compared to non-open access publications (22,23,24,25). Together, these findings highlight the importance of collaboration, institutional reputation, and research accessibility in enhancing scientific impact. Despite the significance of these findings, certain limitations should be acknowledged. Firstly, the study focused only on the top five transplantation journals, which may not be representative of the entire field. The findings may not be applicable to journals outside of this sample. Secondly, the study only considered articles published in 2019 and 2020, limiting the temporal scope of the analysis. Future research could incorporate a broader range of publication years to capture any potential trends or changes over time. Additionally, the study relied on citation counts as a measure of impact, which may not fully capture the influence or quality of an article. Other indicators could provide a more comprehensive assessment of impact.

Conclusion:

This analysis delineates essential elements that enhance the visibility and influence of journals at the forefront of transplantation research. Articles characterized by extensive author collaborations, open-access availability, and contributions from leading organizations were more likely to influence their citation performance. The significance of subjects such as COVID-19 and kidney transplantation further illustrates how temporal and thematic relevance can influence scholarly impact within a specific context. These insights underscore the role of drivers of influence in transplantation research. Future investigations should include a wider journal selection and extended timeline to validate the generalizability of the findings and to promote interdisciplinary viewpoints to enhance the quality and impact of publications.