Abstract
Purpose
Although several randomized controlled trials (RCTs) have examined the efficacy of rotavirus vaccines, few have comprehensively assessed their reporting quality and risk of bias. This study aimed to evaluate the reporting quality and methodological rigor of RCTs on rotavirus vaccines using the CONsolidated Standards Of Reporting Trials (CONSORT) 2010 checklist and the Cochrane Risk of Bias 2.0 (RoB 2.0) tool.
Materials and Methods
We systematically searched PubMed and Cochrane Central for phase 3 randomized controlled trials of rotavirus vaccines administered as monotherapy. Reporting quality was assessed using the CONSORT 2010 checklist and risk of bias was evaluated with the Cochrane RoB 2.0 tool across five domains to determine overall methodological rigor.
Results
A total of 29 phase 3 RCTs were included after screening 1,066 records. Most trials were conducted in Asia and funded by industry. Adherence to the CONSORT 2010 checklist was high for trial design and outcome reporting but poor for protocol availability, allocation concealment, and blinding procedures. Overall, 62% of studies had a low risk of bias, while 34% were rated high. Trials published after 2010 and those with low risk of bias showed significantly higher reporting quality.
Conclusion
Adherence to the CONSORT 2025 guidelines is essential for future rotavirus vaccine trials, enhancing the quality of individual studies while reinforcing the broader evidence base that informs immunization strategies and public health policies.
Keywords: Rotavirus, Randomized controlled trial, Bias, Guideline adherence
INTRODUCTION
Rotavirus infection is a leading cause of acute gastroenteritis in children under five years of age worldwide, often resulting in severe dehydration [1,2]. In 2006, the World Health Organization (WHO) recommended the inclusion of rotavirus vaccines in immunization programs in the Americas and Europe and extended this recommendation globally in 2009 [3]. Currently, four vaccines have WHO prequalifications, of which Rotarix and RotaTeq are the most widely used. Substantial reductions in severe diarrhea and rotavirus-related hospitalizations have been reported in countries that have adopted routine childhood vaccinations [4]. Nevertheless, the disease burden remains high in low- and lower-middle-income countries, where mortality is high and vaccine effectiveness is modest [5,6]. Understanding and addressing the reasons for this heterogeneity are critical.
Randomized controlled trials (RCTs) are considered the gold standard for evaluating medical interventions [7]. However, the reliability of their findings depends not only on a robust study design but also on methodological rigor and transparency in reporting [8,9]. Concerns regarding inadequate and inconsistent trial reporting led to the development of the CONsolidated Standards Of Reporting Trials (CONSORT) statement in 1996, with subsequent revisions in 2001 and 2010 [10,11,12]. CONSORT provides a structured checklist, flow diagram, and explanatory guidance to improve the completeness and clarity of RCT reporting and is now widely required by peer-reviewed journals.
Nevertheless, completeness of reporting alone does not ensure methodological quality. Therefore, the Cochrane Collaboration developed the revised Risk of Bias tool (RoB 2.0), which evaluates five domains: randomization process, deviations from intended interventions, missing outcome data, outcome measurement, and selection of reported results [13]. By providing standardized signaling questions and structured judgments, Cochrane RoB 2.0, which supports a consistent evaluation of internal validity, is widely applied in systematic reviews and meta-analyses.
Rotavirus vaccines provide a particularly appropriate context for evaluating reporting quality and risk of bias in randomized controlled trials. Research on rotavirus vaccines has accumulated over an extended period, from early trials conducted during initial vaccine introduction to more recent studies performed under increasingly standardized regulatory and reporting frameworks. This long research history allows examination of how reporting practices have evolved over time, particularly in relation to the adoption of reporting guidelines such as the CONSORT statement. As a result, rotavirus vaccine trials offer a valuable opportunity to assess reporting quality within a well-established and policy-relevant area of vaccine research.
Although numerous RCTs have examined the efficacy of rotavirus vaccines, few have comprehensively assessed their reporting quality and risk of bias. Given that vaccine trials involve healthy populations, transparent reporting of adverse events is critical for public health decision-making and regulatory evaluation [14]. In this study, we aimed to evaluate the reporting quality and methodological rigor of RCTs on rotavirus vaccines using the CONSORT 2010 checklist and the Cochrane RoB 2.0 tool.
MATERIALS AND METHODS
Study selection and eligibility criteria
We systematically searched PubMed and Cochrane Central using the following search terms: (“Rota” OR “Rotavirus”) AND (“vaccine” OR “vaccines” OR “vaccination”) AND (“randomized controlled trials” OR “randomization” OR “RCT”).
Eligible studies were phase 3 RCTs of rotavirus vaccines administered as monotherapy. Trials were included if efficacy was the primary outcome, or if safety was the primary outcome but efficacy was reported as a secondary endpoint. When the study phase was not explicitly stated, the trials were included only if efficacy was clearly defined as the primary outcome. Review articles, case reports, clinical guidelines, and observational studies, such as cohort, case-control, and cross-sectional studies, were excluded. Studies based on non-human data, including in vitro experiments, in silico simulations, and animal models, were excluded. Trials conducted exclusively in human immunodeficiency virus-infected populations were also excluded if efficacy was not the primary endpoint. In addition, studies evaluating co-administration with other vaccines, vaccine formulations, or comparative effectiveness were excluded unless efficacy was designated as the primary outcome.
Data extraction
The following data were extracted from each included study: title, journal, year of publication, country, vaccine type, sample size, and funding sources. Countries were categorized into 4 groups: Europe, North America, Asia, and others. For multi-country trials, each country was counted separately. Vaccine types were categorized as Rotarix, RotaTeq, or others. Funding sources were classified as either industrial or public, and trials with both sources were counted in both categories. If funding was not reported or unclear, it was categorized as unreported. Reporting quality, in relation to compliance with the CONSORT guidelines, was evaluated using the CONSORT 2010 checklist. Each item was scored as 1 (clearly and completely reported) or 0 (absent/unclear). Percentage adherence was calculated as the total score divided by the number of applicable items.
Assessment of risk of bias
Risk of bias was evaluated using the Cochrane RoB 2.0 tool for randomized trials, in accordance with the guidelines outlined in the Cochrane Handbook for Systematic Reviews of Interventions. The tool assesses 5 domains: randomization process, deviations from intended interventions, missing outcome data, measurement of outcomes, and selection of reported results. Each domain was judged using structured signaling questions and classified as “Low risk,” “Some concerns,” or “High risk,” according to the decision algorithms of the RoB 2.0 framework. The overall risk of bias rating was then assigned as “Low” when all domains were judged low, “Some concerns” when at least one domain raised concerns, but none were high, and as “High” when one or more domains were rated high or when multiple domains raised concerns that substantially reduced confidence in the results.
Statistical analysis
Descriptive statistics were used to summarize the study characteristics, and mean values were compared between the groups. Variance homogeneity was tested using the F-test, followed by the Student’s t-test, as appropriate. All analyses were 2-tailed, with p<0.05 considered statistically significant.
RESULTS
The initial search conducted in December 2025 identified a total of 1,066 articles, including 560 articles from PubMed and 506 from PubMed Central. After removing 258 duplicates, 808 articles underwent title and abstract screening. Of these, 591 were excluded based on title and abstract screening, leaving 217 articles for full-text screening. Following full-text review, 188 articles were excluded, resulting in the final inclusion of 29 articles (Fig. 1).
Fig. 1. Flow chart of the article selection process.
Characteristics of included trials
Table 1 summarizes the characteristics of the 29 included studies. Most of the trials (41.4%) were published between 2001 and 2010, while 27.6% were published before 2000 and 31.0% were published after 2011. The majority of RCTs were conducted in Asia (41.4%), followed by others (37.9%), North America (13.8%), and Europe (20.7%). Regarding the type of rotavirus vaccine administered, 31.0% received Rotarix, 20.7% received RotaTeq, and the remaining 48.3% were categorized as others. Sample sizes varied, with 58.6% of the trials enrolling more than 1,000 participants, 27.6% enrolling 1–500 participants, and 13.8% enrolling 500–1,000 participants. More than half of the trials (65.5%) received funding from industry sources, 41.4% were funded by public sources, and 6.9% did not report any funding information.
Table 1. Study characteristics (N=29).
| Characteristics | Values | |
|---|---|---|
| Year of publication | ||
| Before 2000 | 8 (27.6) | |
| 2001–2010 | 12 (41.4) | |
| After 2011 | 9 (31.0) | |
| Region | ||
| Europe | 6 (20.7) | |
| North America | 4 (13.8) | |
| Asia | 12 (41.4) | |
| Others | 11 (37.9) | |
| Intervention | ||
| Rotarix | 9 (31.0) | |
| Rotateq | 6 (20.7) | |
| Others | 14 (48.3) | |
| Sample size | ||
| 1–500 | 8 (27.6) | |
| 500–1,000 | 4 (13.8) | |
| >1,000 | 17 (58.6) | |
| Funding | ||
| Public | 12 (41.4) | |
| Industry | 19 (65.5) | |
| Unreported | 2 (6.9) | |
Values are presented as number of studies (%).
Adherence to the CONSORT statement
Adherence of the 29 included RCTs to the CONSORT 2010 checklist varied substantially across individual items (Table 2). Full adherence (100%) was observed for several key items, including the structured abstract, scientific background or objectives, description of intervention similarities, and interpretation. Near-complete adherence (≥97%) was also noted for reporting of trial design, eligibility criteria, study setting, intervention details, outcome definitions, and harms.
Table 2. Reporting compliance rates for CONSORT items.
| Section/Topic | Item No. | Checklist item | % | |
|---|---|---|---|---|
| Title and abstract | ||||
| 1a | Identification as a randomized trial in the title | 38 | ||
| 1b | Structured summary of trial design, methods, results, and conclusions (for specific guidance, see CONSORT for abstracts) | 100 | ||
| Introduction | ||||
| Background and objectives | 2a | Scientific background and explanation of rationale | 100 | |
| 2b | Specific objectives or hypotheses | 100 | ||
| Methods | ||||
| Trial design | 3a | Description of trial design (such as parallel, factorial), including allocation ratio | 97 | |
| 3b | 0 | |||
| Participants | 4a | Eligibility criteria for participants | 97 | |
| 4b | Settings and locations where the data were collected | 97 | ||
| Interventions | 5 | The interventions for each group, with sufficient details to allow replication, including how and when they were actually administered | 97 | |
| Outcomes | 6a | Completely defined pre-specified primary and secondary outcome measures, including how and when they were assessed | 76 | |
| 6b | Any changes to trial outcomes after the trial commenced, with reasons | 0 | ||
| Sample size | 7a | How the sample size was determined | 69 | |
| 7b | When applicable, an explanation of any interim analyses and stopping guidelines | 0 | ||
| Randomization: | ||||
| Sequence generation | 8a | Method used to generate the random allocation sequence | 66 | |
| 8b | Type of randomization; details of any restriction (such as blocking and block size) | 55 | ||
| Allocation concealment mechanism | 9 | Mechanism used to implement the random allocation sequence (such as sequentially numbered containers), describing any steps taken to conceal the sequence until interventions were assigned | 45 | |
| Implementation | 10 | Who generated the random allocation sequence, who enrolled participants, and who assigned participants to interventions | 45 | |
| Blinding | 11a | If done, who was blinded after assignment to interventions (for example, participants, care providers, those assessing outcomes) and how | 52 | |
| 11b | If relevant, a description of the similarity of interventions | 100 | ||
| Statistical methods | 12a | Statistical methods used to compare groups for primary and secondary outcomes | 93 | |
| 12b | Methods for additional analyses, such as subgroup analyses and adjusted analyses | 93 | ||
| Results | ||||
| Participants flow (a diagram is strongly recommended) | 13a | For each group, the number of participants who were randomly assigned, received intended treatment, and were analyzed for the primary outcome | 69 | |
| 13b | For each group, losses and exclusions after randomization, together with reasons | 79 | ||
| Recruitment | 14a | Dates defining the periods of recruitment and follow-up | 41 | |
| 14b | Why the trial ended or was stopped | 0 | ||
| Baseline data | 15 | Table showing baseline demographic and clinical characteristics for each group | 55 | |
| Numbers analyzed | 16 | For each group, the number of participants (denominator) included in each analysis, and whether the analysis was by the original assigned groups | 55 | |
| Outcomes and estimation | 17a | For each primary and secondary outcome, results for each group, and the estimated effect size and its precision (such as 95% confidence intervals). For binary outcomes, presentation of both absolute and relative effect sizes is recommended | 90 | |
| 17b | For binary outcomes, presentation of both absolute and relative effect sizes is recommended | 45 | ||
| Ancillary analyses | 18 | Results of any other analyses performed, including subgroup analyses and adjusted analyses, distinguishing pre-specified from exploratory | 93 | |
| Harms | 19 | All important harms or unintended effects in each group (for specific guidance, see CONSORT for harms) | 97 | |
| Discussion | ||||
| Limitations | 20 | Trial limitations, addressing sources of potential bias, imprecision, and, if relevant, multiplicity of analyses | 38 | |
| Generalizability | 21 | Generalizability (external validity, applicability) of the trial findings | 86 | |
| Interpretation | 22 | Interpretation consistent with results, balancing benefits and harms, and considering other relevant evidence | 100 | |
| Other information | ||||
| Registration | 23 | Registration number and name of trial registry | 59 | |
| Protocol | 24 | Where the full trial protocol can be accessed, if available | 3 | |
| Funding | 25 | Sources of funding and other support (such as supply of drugs), role of funders | 93 | |
CONSORT, CONsolidated Standards Of Reporting Trials.
Several items exhibited moderate to high adherence. Sample size calculations (69%), participant flow (69%), and losses after randomization (79%) were commonly reported. Statistical methods for outcomes and additional analyses were well documented (93%), as were outcome estimates (90%), ancillary analyses (93%), funding sources (93%), and generalizability (86%).
In contrast, several items were poorly reported. Only 3% of the trials reported protocol availability. Allocation concealment and randomization implementation were described in 45% of the studies, and blinding procedures were reported in 52%. The baseline characteristics and analysis population were reported in 55% of the trials, respectively. Recruitment period (41%), absolute and relative effect sizes for binary outcomes (45%), and study limitations (38%) were also frequently underreported.
Risk of bias assessment
Upon evaluating the overall risk of bias, 18 studies (62%) were judged to have a low risk of bias, only 1 study (3%) demonstrated some concern, and 10 studies (34%) were categorized as having a high risk of bias overall (Table 3).
Table 3. Summary of risk assessment of bias according to the Cochrane RoB 2.0 tool.
| No. | Authors | Risk of bias domains | |||||
|---|---|---|---|---|---|---|---|
| D1 | D2 | D3 | D4 | D5 | Overall | ||
| 1 | Flores et al. (1987) | Low | High | High | Low | Some | High |
| 2 | Lanata et al. (1989) | Low | High | High | High | Some | High |
| 3 | Lanata et al. (1996) | Low | Some | High | High | Some | High |
| 4 | Linhares et al. (1996) | Low | High | High | High | Some | High |
| 5 | Joensuu et al. (1997) | Low | Low | Low | High | Some | High |
| 6 | Perez-Schael et al. (1997) | Low | High | High | Low | Some | High |
| 7 | Santosham et al. (1997) | Low | Low | High | High | Some | High |
| 8 | Bernstein et al. (1999) | Low | Low | Low | High | Some | High |
| 9 | Clark et al. (2004) | Low | Low | Low | Low | Some | Some |
| 10 | Vesikari et al. (2004) | Low | Low | High | Low | Some | High |
| 11 | Ruiz-Palacios et al. (2006) | Low | Low | Low | Low | Low | Low |
| 12 | Vesikari et al. (2006) (Vaccine 24) | Low | Low | High | Low | Some | High |
| 13 | Vesikari et al. (2006) (NEJM) | Low | Low | Low | Low | Some | Low |
| 14 | Vesikari et al. (2007) | Low | Low | Low | Low | Some | Low |
| 15 | Chang et al. (2009) | Low | Low | Low | Low | Low | Low |
| 16 | Narang et al. (2009) | Low | Low | Low | Low | Low | Low |
| 17 | Phua et al. (2009) | Low | Low | Low | Low | Low | Low |
| 18 | Armah et al. (2010) | Low | Low | Low | Low | Low | Low |
| 19 | Madhi et al. (2010) | Low | Low | Low | Low | Low | Low |
| 20 | Zaman et al. (2010) | Low | Low | Low | Low | Low | Low |
| 21 | Kawamura et al. (2011) | Low | Low | Low | Low | Low | Low |
| 22 | Armah et al. (2013) | Low | Low | Low | Low | Low | Low |
| 23 | Iwata et al. (2013) | Low | Low | Low | Low | Low | Low |
| 24 | Bhandari et al. (2014) | Low | Low | Low | Low | Low | Low |
| 25 | Li et al. (2014) | Low | Low | Low | Low | Low | Low |
| 26 | Isanaka et al. (2017) | Low | Low | Low | Low | Low | Low |
| 27 | Kulkarni et al. (2017) | Low | Low | Low | Low | Low | Low |
| 28 | Mo et al. (2017) | Low | Low | Low | Low | Low | Low |
| 29 | Xia et al. (2020) | Low | Low | Low | Low | Low | Low |
Each domain was judged using structured signaling questions and classified as: “Low” = Low risk, “Some” = Some concerns, “High” = High risk.
Most studies demonstrated a low risk of bias across the majority of domains, with the “Randomization process” and “Measurement of the outcome” domains showing particularly robust performance, as evidenced by the predominance of “Low risk” ratings. However, variability was observed in other domains. Specifically, a substantial proportion of studies were rated as having either “Some concerns” or “High risk” in domains such as “Deviations from intended interventions,” “Missing outcome data,” and “Selection of the reported result.”
Factors associated with reporting quality
Several factors were associated with overall reporting quality, as assessed by the CONSORT checklist (Table 4). Studies published after 2010 demonstrated significantly higher reporting quality than those published earlier, with a mean adherence rate of 85.5% (95% confidence interval [CI], 81.7–89.3; p=0.00002). Furthermore, studies that received a “Low risk” rating in the risk of bias assessment exhibited significantly better adherence to reporting standards, with a mean adherence rate of 62.7% (95% CI, 55.9–69.5; p=0.002). Conversely, other factors, including the source of funding and whether the study was conducted in a single country or across multiple countries, were not significantly associated with reporting quality.
Table 4. Factors associated with key elements of the CONSORT guidelines.
| Characteristic | Categories used for the characteristic | Reporting quality (%) | p-value |
|---|---|---|---|
| Mean (95% CI) | |||
| Number of participating countries | Single | 71.2 (62.6–77.8) | Ref |
| Multi | 80.1 (71.1–89.1) | 0.15 | |
| Year of publication | ≤2000 | 62.9 (54.6–71.2) | Ref |
| 2001–2010 | 71.2 (61.7–80.8) | 0.19 | |
| ≥2011 | 85.5 (81.7–89.3) | <0.001 | |
| Risk of bias | Low and some concern | 78.9 (72.6–85.3) | Ref |
| High | 62.7 (55.9–69.5) | 0.002 | |
| Type of funding | Public, missing | 69.3 (55.6–83.0) | Ref |
| Industry | 72.2 (65.0–79.4) | 0.66 | |
| Both | 86.3 (73.6–99.1) | 0.08 |
CONSORT, CONsolidated Standards Of Reporting Trials; CI, confidence interval.
DISCUSSION
The objective of the current study was to assess the reporting adherence of RCTs evaluating the efficacy of rotavirus vaccines. Reporting quality and risk of bias were evaluated using CONSORT 2010 and RoB 2.0, respectively, to determine the overall level of transparency and reliability [12,15]. Across the included studies, average adherence to the CONSORT checklist was approximately 70%, with substantial variation across individual items. Notably, key methodological components such as randomization, blinding, and sample size calculation were often inadequately reported. Likewise, the risk of bias assessment revealed high risk in several domains, indicating the need for improvement in both study design and reporting practices.
In this study, an analysis of RCTs based on the CONSORT guidelines revealed that several studies showed low adherence to the “Title” item. The title is the first piece of information encountered by the readers and serves as a key element in clearly conveying the nature of the study. It should be explicitly stated that the study was a randomized controlled trial, thereby facilitating proper classification, searchability, and appraisal of evidence. Failure to include this element may diminish the visibility and discoverability of a study [5,16]. In contrast, items related to the abstract and statements of the study objectives showed relatively high adherence.
Most included RCTs provided sufficient details on the trial design, participants, interventions, outcomes, and statistical methods. However, critical methodological components, including sample size calculation, randomization, and blinding, were reported in approximately 50% of the RCTs, indicating substantial gaps in transparency and compliance.
Appropriate sample size calculation ensures a valid study design and sufficient statistical power. In its absence, studies may be underpowered or overpowered, potentially leading to unreliable conclusions [17]. Incomplete reporting of randomization, including sequence generation and allocation concealment, increases the risk of selection bias and compromises the internal validity [18]. Lack of detail regarding blinding, specifically, who was blinded and how, limits the assessment of outcome objectivity and increases the potential for information bias [19,20]. Additionally, the absence of recruitment or follow-up period reporting impairs the readers’ ability to assess temporal relevance, seasonal effects, and potential changes in clinical practice during the trial period. Similarly, failure to present baseline characteristics restricts the ability to judge comparability between groups after randomization, which is essential for accurately interpreting treatment effects.
In this study, nearly all included RCTs scored poorly on the “protocol” item of the CONSORT checklist, raising substantial concerns regarding transparency and reproducibility. When protocols are not clearly reported or are prospectively registered, investigators may be more likely to modify the analysis plan or selectively report favorable outcomes. Such selective reporting undermines the internal validity of the study and introduces bias in the interpretation of the results [21].
Study protocols define the study design, primary outcomes, and statistical analysis plans in advance, ensuring consistency in trial conduct and serving as a critical reference for external verification and evidence synthesis [22]. Therefore, the CONSORT guidelines emphasize the importance of prospective protocol registration and full reporting. Failure to meet these standard limits the credibility and applicability of trial findings in clinical practice.
Our risk of bias analysis revealed notable deficiencies in specific domains, particularly in domains of missing outcome data and the selection of reported results. In our study, 28% of the trials were assessed to have a high risk of bias in the missing outcome data domain, whereas 45% were judged to have some concerns in the selection domain of the reported results. When clinical trials are categorized as having a risk of bias, their ability to draw reliable conclusions is substantially compromised. This, in turn, can undermine the credibility of the clinical practice guidelines based on such evidence.
Our subgroup analysis further revealed that certain factors were associated with higher reporting quality. Studies published after 2010 demonstrated significantly better adherence to CONSORT criteria (mean, 85.5%; 95% CI, 81.7–89.3; p<0.001), likely reflecting the influence of updated reporting guidelines and journal policies requiring checklist submission. Moreover, trials rated as “Low risk” in the risk of bias assessment demonstrated significantly better reporting quality (mean, 62.7%; 95% CI, 55.9–69.5; p=0.002). In contrast, neither the source of funding nor the trial setting, whether single-country or multi-country, was significantly associated with reporting adherence.
The recent revision of the CONSORT guidelines, from the 2010 version to the 2025 update, reflects a notable shift toward improved transparency, methodological compliance, and inclusivity in the reporting of RCTs [23]. These changes are particularly relevant for future studies evaluating the efficacy and safety of rotavirus vaccines and should be proactively incorporated into study planning and reporting frameworks.
The updated guidelines underscore the importance of equity in clinical research. Vaccine responses may differ across population subgroups defined by race, ethnicity, socioeconomic status, and healthcare accessibility [24,25,26]. CONSORT 2025 encourages the systematic collection and reporting of such variables and highlights the need for subgroup analyses to assess differential effects. Accordingly, future rotavirus vaccine RCTs should be designed to capture comprehensive demographic data and consider equity-oriented analyses to enhance the applicability of the findings across diverse populations.
Notably, the CONSORT 2025 update introduces refinements directly relevant to future vaccine trials. Key emphases include enhanced transparency in reporting, systematic consideration of equity across populations, and clear documentation of long-term follow-up and data sharing. The guidelines further state that any use of digital or automated tools in data collection or analysis should be reported transparently. More importantly, equity-oriented reporting is highly relevant because vaccine responses and access can vary across subgroups defined by socioeconomic status, geography, and healthcare availability. Similarly, the durability of protection and potentially delayed adverse events make long-term follow-up essential, and clear documentation of follow-up procedures should be prioritized. Finally, explicit plans for sharing data and analysis scripts are recommended to enhance reproducibility and facilitate evidence synthesis. Incorporating these practices into future rotavirus vaccine RCTs will improve methodological rigor and ensure that the findings are credible and applicable across diverse populations.
Recent revisions of the CONSORT guidelines represent a crucial step toward more accountable, inclusive, and methodologically rigorous clinical research. Ensuring the integrity and transparency of published data has become increasingly critical in the context of ongoing development and evaluation of rotavirus vaccines [27,28]. Transparent and comprehensive reporting not only facilitates the accurate interpretation of trial findings but also enables subsequent researchers to build upon established evidence with confidence and reliability.
Therefore, adherence to the CONSORT 2025 guidelines is essential for future rotavirus vaccine trials, enhancing the quality of individual studies while simultaneously reinforcing the broader evidence base that informs immunization strategies and public health policies. To this end, the principles outlined in CONSORT 2025 should be regarded as fundamental components throughout the clinical trial lifecycle, encompassing the initial protocol development, study implementation, and final dissemination of results.
This study had several limitations. First, only articles published in English were included; relevant studies conducted in non-English-speaking regions were excluded from the analysis. Second, this study assessed the CONSORT and risk of bias criteria solely based on reported information, which may not fully reflect the actual conduct of the trials. Incomplete reporting may have led to lower scores despite the methodologically sound study execution. Third, this study did not evaluate the clinical efficacy or safety of the vaccines. Therefore, these findings should not be interpreted as direct evidence of vaccine effectiveness or safety. Fourth, the evaluation criteria were based on the CONSORT 2010 guidelines, and more recent updates were not included in the analysis. Fifth, the protocol of the present study was not formally registered, which may have limited the transparency of the review process. However, this study was conducted in accordance with established methodological guidelines for systematic reviews. Finally, all assessments were conducted by a single reviewer, which may have introduced subjectivity and potential bias into the evaluation process.
Nevertheless, this study is meaningful because it systematically analyzed the reporting quality of RCTs evaluating the efficacy of rotavirus vaccines. These findings highlight both areas of strength and opportunities for improvement in current reporting practices and may serve as a valuable reference for future efforts to enhance the quality of clinical trial reporting.
Footnotes
Funding: None.
Conflict of Interest: No potential conflict of interest relevant to this article was reported.
- Conceptualization: Cho J.
- Data curation: Kim J.
- Investigation: Kim J.
- Supervision: Cho J.
- Writing - original draft: Kim J.
- Writing - review & editing: Cho J.
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