Introduction

Real-world data (RWD) has garnered growing interest in the oncology community in addressing clinical and policy-relevant queries that cannot be resolved with clinical trial (CT) data [1]. Although randomized controlled trials (RCTs) are the accepted gold standard for generating clinical evidence [2], the controlled research settings, resource intensiveness, and limited follow-up duration restrict their generalizability to real-world clinical practice [2–4]. In contrast, real-world evidence (RWE) provides insights in a short time with lesser resources and reduced costs compared to RCTs [2].

Recently, there have been significant investments in electronic health record (EHR) capabilities for oncology data collection, leading to databases with very large sample sizes [5]. Furthermore, RWD sources such as EHRs of treatment and outcomes linked to cancer registry data provide insights into patients, treatments, and related outcomes in routine oncology practice [1]. Real-world issues addressed by RWE studies in diverse geographic and/or economic contexts include cancer burden, access to cancer care, quality of care and/or adherence, long-term safety, efficacy, and cost-effectiveness [1,3,4]. Additionally, RWE studies can describe treatment efficacy and tolerability in special patient populations which are either under-represented or excluded from RCTs [4].

While RWE is becoming increasingly important in healthcare decision-making, its value is still not always recognized. RWE studies complement RCTs by providing insights with a high degree of external validity as well as for a better understanding of the biological effects of a drug in different settings [2,6]. Despite the increasing presence of RWE in oncology, there remains a paucity of studies comparing the RWE landscape with CTs and evaluating the factors associated with their high-tier acceptance at scientific conferences, particularly in gynecologic cancers. Analyzing the type of research accepted, the number of abstracts, their trends and characteristics, and the tier of presentations at key oncology conferences can help understand the priority of these scientific presentations, thus allowing for better dissemination of different types of research.

Prior studies have focused on assessing the publication patterns of oncology and/or hematology abstracts presented at major conferences to identify the factors that influence their publication rates [7–11]. Previous meta-research by Frank et al., 2022 evaluated the association of accuracy estimates, abstract conclusion positivity, and completeness of abstract reporting with acceptance at radiology conferences [12]. A careful evaluation of the trends of abstract presentation is critical as they have the potential to influence clinical decision-making and research [13]. Hence, the primary objective of this study is to evaluate the proportion of RWE versus CT abstracts presented at two annual oncology conferences, the American Society of Clinical Oncology (ASCO) and the Society of Gynecologic Oncology (SGO). The secondary objectives are to describe the distribution and trends of RWE abstracts and the tier of acceptance for RWE versus CT and to analyze the association between RWE abstract characteristics and the different tiers of acceptance.

Methods

Results

Distribution and trends of RWE and CT abstracts

A total of 3163 abstracts were screened, of which 2271 were included in the analysis (RWE abstracts, n = 1756 [77.32%]; CTs, n = 515 [22.68%]). The proportion of RWE abstracts was higher at SGO compared with ASCO (69.99% vs 30.01%), while CT abstracts represented a higher proportion of abstracts from ASCO compared with SGO (72.43% vs 27.57%; p < 0.001 for both). Overall, there was an increasing trend of RWE abstract acceptance from 2018 to 2020 (2018 vs 2019 vs 2020: 27.16% vs 33.6% vs 39.24%; p < 0.001) (Table 1). Of abstracts accepted overall, the number of total abstracts increased by 10.52%, the proportion of RWEs by 9.34%, and the proportion of CTs by 1.19% from 2018 to 2020. In general, abstracts on ovarian cancer represented a higher proportion of those accepted than abstracts on other gynecologic cancer types (p < 0.001). Additionally, the proportion of RWE abstracts on ovarian cancer was higher compared with other cancer types; whereas among CTs, the highest were on multiple cancers versus all the gynecological cancer types studied (p < 0.001 for both) (Table 1).

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Table 1. Distribution of abstracts stratified by CT and RWE, conference, year of publication, cancer type, and tier of acceptance.

https://doi.org/10.1371/journal.pone.0321654.t001

Overall, the majority of the abstracts (71.42%) were accepted as poster sessions compared with other tiers of acceptance (p < 0.001). A greater proportion of RWE abstracts compared with CTs were accepted as posters (74.89% vs 59.61%) or publication only/abstract (18.68% vs 11.07%), and fewer as oral presentations (3.93% vs 19.61%; p < 0.001 for all) (Table 1).

Further, at ASCO, the majority of the RWE abstracts were accepted as publication only/abstract compared with CTs; CTs were accepted more often as poster sessions and oral presentations than RWE across various cancer types assessed (p < 0.001 for all) (Table 2). However, at SGO, a higher proportion of RWE abstracts were accepted as poster sessions compared to CTs (Table 2).

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Table 2. Proportion of CTs versus RWE abstracts accepted at ASCO and SGO by year of publication, cancer type, and tier of acceptance.

https://doi.org/10.1371/journal.pone.0321654.t002

Among the RWE studies, 53.47% were conducted at single sites, 90.03% had academic authorship, and two-thirds (67.65%) of the data sources of the abstracts were from North America (S1 Fig).

Characteristics of RWE abstracts

Data types.

Overall, data from other clinical data sources were most frequently utilized in RWE abstracts (44.59%), followed by other data repositories (21.53%) and medical records (6.66%;

p < 0.001 for all; Table 3). About three-quarters of the RWE studies that included data from other clinical data sources were presented as poster sessions (74.58%), followed by publication only/abstracts (19.03%). Overall, there was no statistically significant association between the type of data used and the tier of presentation (p = 0.25) (S2 Table).

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Table 3. Distribution of RWE abstracts by type of data collected and cancer type.

https://doi.org/10.1371/journal.pone.0321654.t003

Statistical significance of results.

Of the RWE abstracts analyzed, nearly one-third reported statistically significant results while only a few contained no statistically significant results (32.35% vs 6.38%; p < 0.001). Furthermore, 31.49% of RWE abstracts did not report a statistical analysis of results, and the proportion of these RWE studies was higher at ASCO compared with SGO (41.18% vs 27.34%; p < 0.001) (Table 4). Most of the RWE abstracts were accepted as poster sessions regardless of the statistical significance (p < 0.001 for all) (Table 4). However, in SGO, the majority of the abstracts that reported statistically significant results (92.7%) were accepted as poster sessions versus other tiers of acceptance, whereas in ASCO, more than half (59.06%) of the RWE abstracts with statistically significant results were accepted as publication only/abstract (p < 0.001 for both) (Table 4).

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Table 4. Distribution of RWE abstracts by conference, statistical significance of results, and tier of acceptance.

https://doi.org/10.1371/journal.pone.0321654.t004

Type of analysis.

In general, RWE abstracts with a retrospective study design or analyses represented a greater proportion of the accepted RWE abstracts than the prospective study design (59.97% vs 9.4%). Retrospective RWEs were more represented at SGO than ASCO (64.36% vs 49.72%); while prospective abstracts represented similar proportions of accepted work at both conferences. Overall, RWE abstracts related to diagnosis (16.0%) represented a high proportion of accepted work, followed by PROs (4.10%), and economic models (1.65%) (Table 5). Among retrospective RWEs (n = 1053), the majority of the abstracts (78.25%) were presented as poster sessions followed by publication only/abstract (16.52%) and orals (3.13%; p < 0.01). In contrast, RWE abstracts on economic models (n = 29) were represented more as orals than publication only/abstract (17.24% vs 10.34%; p < 0.01) (S3 Table) and were presented more at SGO than ASCO (n = 23 [1.87%] vs n = 6 [1.14%]) (Table 5). Furthermore, 80.7% of RWE abstracts on survival were presented as posters and only 3.51% as orals (S3 Table).

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Table 5. Distribution of RWE abstracts by conference, type of analysis, and cancer type.

https://doi.org/10.1371/journal.pone.0321654.t005

Outcomes assessed.

The most common outcome(s) assessed in RWE abstracts were molecular analyses (17.71%), followed by survival/efficacy (12.98%) and molecular analyses/survival (6.72%). About 6.32% and 3.36% of abstracts focused on screening and economic outcomes, respectively (S4 Table). Among the various cancer types analyzed, molecular analyses were the most frequently evaluated outcomes in multiple cancer abstracts (30.91%). RWE abstracts on specific gynecological cancers analyzed the survival/efficacy outcome more compared with those on multiple cancers (cervical vs ovarian vs endometrial vs multiple: 13.54% vs 15.36% vs 16.67% vs 5.85%). Interestingly, screening (14.77%) and the survival outcomes following a surgical intervention (survival/surgery; 9.85%) were commonly assessed within cervical cancer abstracts specifically (p < 0.001 for all comparisons) (S4 Table).

Regardless of the outcomes assessed, the majority of RWE abstracts were accepted as poster sessions. Molecular analyses (n = 311) were more likely to be accepted as poster sessions (n = 213; 68.49%) followed by publication only/abstract (n = 81; 26.05%), and oral presentations (11; 3.54%). Similarly, the majority of the survival/efficacy analyses (n = 228) were accepted as poster sessions (n = 176; 77.19%) followed by publication only/abstract (18.42% [n = 42],) and oral presentation (n = 5 [2.19%]). A higher proportion of abstracts assessing economic (20.34% vs 11.86%), healthcare resource utilization (14.29% vs 0%), efficacy and safety (12.5% vs 6.25%), and perioperative (13.33% vs 0%) outcomes were accepted as orals than publication only/abstract (p < 0.001 for all) (S5 Table).

Discussion

RWE signifies a bridge between the evidence generated in CT programs and routine clinical practice. To the best of our knowledge, this study is the first to document the distribution, trends, and characteristics related to the tier of acceptance of RWE in gynecologic cancers presented at ASCO and SGO. The results showed an increase in the number of overall abstracts presented from 2018 to 2020; RWE abstracts represented a greater proportion of accepted abstracts than CTs, with an increasing trend in their acceptance during this duration. Furthermore, there were notable differences in the acceptance of abstracts between the two conferences. RWE abstracts represented a statistically higher proportion of work at SGO than at ASCO (69.99% vs 30.01%). These differences may be attributed to the distinct focus criteria of the conferences. SGO concentrates on gynecologic cancer care and emphasizes the latest scientific advancements and clinical practices specific to this field [14–16]. This aligns with higher acceptance of RWEs, providing valuable insights into real-world clinical outcomes and practices. Moreover, RWE provides a comprehensive view of treatment performance in routine clinical practice, allowing for tailored treatments to individual needs, ultimately improving outcomes and guiding policy decisions [17]. In contrast, ASCO is the largest multidisciplinary oncology conference focusing on the latest advances in clinical cancer research, particularly therapeutics [18–20]. Emphasis on CTs at ASCO highlights its role in presenting innovative clinical research and novel therapeutic approaches across various cancers. The increased acceptance of oncology RWE observed in our study is in line with previous research that reported a higher number of RWE studies between 2015 and 2019 [2]. The challenges of conducting CTs during the COVID-19 pandemic [21], coupled with the transition to virtual conferences might contribute to the higher acceptance of RWE abstracts during the study duration. This shift reflects the research community’s adaptability and the growing reliance on RWE to address emerging healthcare challenges during the pandemic. The rise in RWE abstracts has significant implications, specifically for oncology research. By providing real-world insights into the effectiveness and safety of cancer treatments, treatment patterns, patient outcomes, and health economics, RWE can inform the development of evidence-based treatment guidelines, healthcare decision-making, regulatory decisions [2,22], and reimbursement decisions [23].

Overall and among RWE specifically, ovarian cancer abstracts were the most accepted compared with other cancer types. These results may be attributable to the higher incidence of ovarian cancer population, and/or the latest breakthrough treatment with poly (ADP-ribose) polymerase inhibitors that is rapidly changing the treatment paradigms in ovarian cancer [24]. However, among CTs, most of the abstracts included were of multiple cancers. The majority of the RWE abstracts were from single sites, had academic authorship, and the data source was from North America. Furthermore, utilization of other clinical data sources, studies with statistical significance, retrospective study design, and analysis of molecular and/or survival-based outcomes were also most prevalent within RWE abstracts. Molecular outcomes were commonly reported by multiple cancer abstracts. Interestingly, screening outcomes were more often assessed in cervical cancer abstracts compared to all other cancer types.

Gynecologic cancers represent a significant cause of death worldwide and place a substantial economic and humanistic burden on women and their families [25–28]. Cervical cancer is the second most common gynecologic cancer in the majority of regions, specifically in developing countries, whereas ovarian and uterine cancers occur less frequently [25]. However, ovarian cancer has the worst prognosis and highest mortality rate among all gynecological cancers [29]. High incidence rates of ovarian cancer in the North American and West European regions may be linked to the high prevalence of several established risk factors [25]. In our study, the majority of the RWE abstracts were from North America, particularly on ovarian cancer. Also, the preponderance of retrospective RWEs noted may be due to their economical and time-efficient nature, rapid answerability to queries on adherence, and unanticipated safety concerns [30,31]. However, considering inherent limitations and the possibility of confounding and biases, data from retrospective real-world studies should be interpreted with care and a critical evaluation of their methods [17,30]. Methodological recommendations of the International Society for Pharmacoeconomics and Outcomes Research task force can be used to mitigate the biases and validity threats and to improve the causal inferences from such studies [32,33].

Furthermore, advances in molecular and genetic profiles of cancers have led to increased utilization of targeted therapies for personalized cancer care [34]. Understanding cancer genetics and the identification of predictive biomarkers are necessary to ensure better health for women with gynecologic cancer [35]. In our analysis, molecular outcomes were most commonly assessed in the RWE abstracts, thus demonstrating the increasing importance of this endpoint in research involving the management of gynecologic cancers. Also, RWE studies are useful in providing data on survival outcomes mainly via cancer registries in a shorter duration [1]. In our analysis, survival-based outcomes were the second most assessed, and this could be due to the rapid generation of survival data through various RWD sources. Cervical cancer is considered to be avoidable because of the effective preemptive measures including human papillomavirus vaccination and timely screening and treatment of precancerous lesions [36]. The preponderance of screening outcomes in cervical cancer abstracts noted in this study was not surprising as the guidelines for the management of cervical cancer are available in many countries [37,38].

Posters are an effective method for knowledge transfer at oncology conferences. Significant advantages of posters include availability for a longer duration, discussions, and networking opportunities with the authors leading to collaborations [39,40]. Our study results show that both RWE and CT abstracts were more likely to be accepted as posters, though oral presentations had a major presence among CTs. The higher acceptance of RWE abstracts as posters in this study indicates that they do not always achieve the visibility of CTs. A higher proportion of RWE abstracts were accepted as publication only/abstracts at ASCO (60.34%), while as poster sessions at SGO (91.62%).

Azad et al, reported a statistically significant association between the involvement of multiple institutions and larger population size with the RWE acceptance category for publication only versus oral/poster presentations [41]. In our study, RWE abstracts were more commonly accepted as poster sessions regardless of the various types of data collected, statistical significance, study design, and the outcomes assessed. Statistical analysis is a crucial part of any clinical and translational research [42]. In the present study, nearly one-third of RWE abstracts (31.49%) did not report a statistical analysis of the results, demonstrating a piece of suboptimal information. Reporting statistical analysis in the RWE abstracts can help the readers to determine the robustness of study data and can improve the visibility in the scientific community. To enhance statistical reporting in RWE, it is recommended that conferences include this criterion in the abstract submission guidelines mandating key statistical metrics. These measures may aid in quality improvement, higher-tier acceptance, and wider dissemination of novel RWE findings among the oncology scientific community.

Conclusions

RWE abstract data were more frequently presented than CTs at SGO versus ASCO, indicating their substantial contribution to the gynecologic oncology scientific community. Additionally, RWEs were more likely to be accepted as posters, with a smaller proportion of RWE abstracts accepted as oral presentations versus CTs across conferences and cancer types. RWE abstracts utilizing other clinical data sources, analyzing molecular and/or survival outcomes, and reporting statistically significant results were the most common. The results demonstrate that while RWE studies are prevalent, they may not always achieve the visibility of CTs in providing valuable data for healthcare decision-making. The study findings may guide researchers in understanding the type of abstracts preferred at conferences and how best to disseminate their study results to the oncology community.

Supporting information

Acknowledgments

No person other than the listed authors participated in the study, its design, or its reporting.