Data continue to accumulate indicating that many systematic reviews are methodologically flawed, biased, redundant, or uninformative. Some improvements have occurred in recent years based on empirical methods research and standardization of appraisal tools; however, many authors do not routinely or consistently apply these updated methods. In addition, guideline developers, peer reviewers, and journal editors often disregard current methodological standards. Although extensively acknowledged and explored in the methodological literature, most clinicians seem unaware of these issues and may automatically accept evidence syntheses (and clinical practice guidelines based on their conclusions) as trustworthy. A plethora of methods and tools are recommended for the development and evaluation of evidence syntheses. It is important to understand what these are intended to do (and cannot do) and how they can be utilized. Our objective is to distill this sprawling information into a format that is understandable and readily accessible to authors, peer reviewers, and editors. In doing so, we aim to promote appreciation and understanding of the demanding science of evidence synthesis among stakeholders. We focus on well-documented deficiencies in key components of evidence syntheses to elucidate the rationale for current standards. The constructs underlying the tools developed to assess reporting, risk of bias, and methodological quality of evidence syntheses are distinguished from those involved in determining overall certainty of a body of evidence. Another important distinction is made between those tools used by authors to develop their syntheses as opposed to those used to ultimately judge their work. Exemplar methods and research practices are described, complemented by novel pragmatic strategies to improve evidence syntheses. The latter include preferred terminology and a scheme to characterize types of research evidence. We organize best practice resources in a Concise Guide that can be widely adopted and adapted for routine implementation by authors and journals. Appropriate, informed use of these is encouraged, but we caution against their superficial application and emphasize their endorsement does not substitute for in-depth methodological training. By highlighting best practices with their rationale, we hope this guidance will inspire further evolution of methods and tools that can advance the field.
Replication helps ensure that a genotype-phenotype association observed in a genome-wide association (GWA) study represents a credible association and is not a chance finding or an artifact due to uncontrolled biases. We discuss prerequisites for exact replication; issues of heterogeneity; advantages and disadvantages of different methods of data synthesis across multiple studies; frequentist vs. Bayesian inferences for replication; and challenges that arise from multi-team collaborations. While consistent replication can greatly improve the credibility of a genotype-phenotype association, it may not eliminate spurious associations due to biases shared by many studies. Conversely, lack of replication in well-powered follow-up studies usually invalidates the initially proposed association, although occasionally it may point to differences in linkage disequilibrium or effect modifiers across studies.
Abstract We examined the growth trajectory and impact of COVID-19-related papers in the scientific literature until August 1, 2024 and how the scientific workforce was engaged in this work. Scopus indexed 718,660 COVID-19-related publications. As proportion of all indexed scientific publications, COVID-19-related publications peaked in September 2021 (4.7%) remained at 4.3-4.6% for another year and then gradually declined, but was still 1.9% in July 2024). COVID-19-related publications included 1,978,612 unique authors: 1,127,215 authors had ≥5 full papers in their career and 53,418 authors were in the top-2% of their scientific subfield based on a career-long composite citation indicator. Authors with >10%, >30% and >50% of their total career citations be to COVID-19-related publications were 376,942, 201,702, and 125,523, respectively. As of August 1, 2024, 65 of the top-100 most-cited papers published in 2020 were COVID-19-related, declining to 24/100, 19/100, 7/100, and 5/100 for the most-cited papers published in 2021, 2022, 2023, and 2024, respectively. Across 174 scientific subfields, 132 had ≥10% of their active influential (top-2% by composite citation indicator) authors publish something on COVID-19 during 2020-2024. Among the 300 authors with highest composite citation indicator specifically for their COVID-19-related publications, 41 were editors or journalists/columnists and another 23 had most of their COVID-19 citations to published items other than full papers (opinion pieces/letters/notes). COVID-19 massively engaged the scientific workforce in unprecedented ways. As the pandemic ended, there has been a sharp decline in the overall volume and high impact of newly published COVID-19-related publications. Significance statement COVID-19 massively mobilized the scientific workforce. Between 2020 and 2024, over 700,000 papers were published on COVID-19, including 2 million different authors. Across science, almost a third of authors at the top-2% of citation impact in their subfield published on COVID-19. There was a sharp decline in the proportion of COVID-19 papers across science after 2022 and an even more sharp decline in the proportion of COVID-19 papers reaching the highest level of citations. Authors with the highest COVID-19 citation impact prominently included many who were editors, journalists/columnists and opinion writers publishing massively. While other epidemics also witnessed sharp increases and subsequent decline in interest, the magnitude of the covidization and decovidization process is unique in the scientific literature to-date.
The shared memory research community has proposed many complex communication protocols that aim to eliminate specific performance bottlenecks, while still providing an easy-to-use communication interface. Although tailored protocols can eliminate some bottlenecks that arise in real applications, removing the cause of the bottleneck through software optimizations and bug fixes is cheaper to implement, faster to fix (once found), and requires no additional support by the hardware beyond a simple shared memory interface. In fact, in our experience, the choice of coherence protocol is much less important than providing an efficient hardware feedback that indentifies the source of the problem. Future cache-coherence research should focus efforts on illuminating memory system behavior, providing smarter tools to identify bottlenecks, and helping to eliminate them through software optimizations.
The CCR5-Delta32 and CCR2-64I alleles had a strong protective effect on progression of HIV-1 infection, but SDF-1 3'A homozygosity carried no such protection.
Currently, there is a growing interest in ensuring the transparency and reproducibility of the published scientific literature. According to a previous evaluation of 441 biomedical journals articles published in 2000-2014, the biomedical literature largely lacked transparency in important dimensions. Here, we surveyed a random sample of 149 biomedical articles published between 2015 and 2017 and determined the proportion reporting sources of public and/or private funding and conflicts of interests, sharing protocols and raw data, and undergoing rigorous independent replication and reproducibility checks. We also investigated what can be learned about reproducibility and transparency indicators from open access data provided on PubMed. The majority of the 149 studies disclosed some information regarding funding (103, 69.1% [95% confidence interval, 61.0% to 76.3%]) or conflicts of interest (97, 65.1% [56.8% to 72.6%]). Among the 104 articles with empirical data in which protocols or data sharing would be pertinent, 19 (18.3% [11.6% to 27.3%]) discussed publicly available data; only one (1.0% [0.1% to 6.0%]) included a link to a full study protocol. Among the 97 articles in which replication in studies with different data would be pertinent, there were five replication efforts (5.2% [1.9% to 12.2%]). Although clinical trial identification numbers and funding details were often provided on PubMed, only two of the articles without a full text article in PubMed Central that discussed publicly available data at the full text level also contained information related to data sharing on PubMed; none had a conflicts of interest statement on PubMed. Our evaluation suggests that although there have been improvements over the last few years in certain key indicators of reproducibility and transparency, opportunities exist to improve reproducible research practices across the biomedical literature and to make features related to reproducibility more readily visible in PubMed.
<p>PDF - 138KB, Total number and total direct cost of all EGRP grants by year.</p>
Space medicine is a vital discipline with often time-intensive and costly projects and constrained opportunities for studying various elements such as space missions, astronauts, and simulated environments. Moreover, private interests gain increasing influence in this discipline. In scientific disciplines with these features, transparent and rigorous methods are essential. Here, we undertook an evaluation of transparency indicators in publications within the field of space medicine. A meta-epidemiological assessment of PubMed Central Open Access (PMC OA) eligible articles within the field of space medicine was performed for prevalence of code sharing, data sharing, pre-registration, conflicts of interest, and funding. Text mining was performed with the rtransparent text mining algorithms with manual validation of 200 random articles to obtain corrected estimates. Across 1215 included articles, 39 (3%) shared code, 258 (21%) shared data, 10 (1%) were registered, 110 (90%) contained a conflict-of-interest statement, and 1141 (93%) included a funding statement. After manual validation, the corrected estimates for code sharing, data sharing, and registration were 5%, 27%, and 1%, respectively. Data sharing was 32% when limited to original articles and highest in space/parabolic flights (46%). Overall, across space medicine we observed modest rates of data sharing, rare sharing of code and almost non-existent protocol registration. Enhancing transparency in space medicine research is imperative for safeguarding its scientific rigor and reproducibility.
Objective To determine the comparative effectiveness of exercise versus drug interventions on mortality outcomes. Design Metaepidemiological study. Eligibility criteria Meta-analyses of randomised controlled trials with mortality outcomes comparing the effectiveness of exercise and drug interventions with each other or with control (placebo or usual care). Data sources Medline and Cochrane Database of Systematic Reviews, May 2013. Main outcome measure Mortality. Data synthesis We combined study level death outcomes from exercise and drug trials using random effects network meta-analysis. Results We included 16 (four exercise and 12 drug) meta-analyses. Incorporating an additional three recent exercise trials, our review collectively included 305 randomised controlled trials with 339 274 participants. Across all four conditions with evidence on the effectiveness of exercise on mortality outcomes (secondary prevention of coronary heart disease, rehabilitation of stroke, treatment of heart failure, prevention of diabetes), 14 716 participants were randomised to physical activity interventions in 57 trials. No statistically detectable differences were evident between exercise and drug interventions in the secondary prevention of coronary heart disease and prediabetes. Physical activity interventions were more effective than drug treatment among patients with stroke (odds ratios, exercise v anticoagulants 0.09, 95% credible intervals 0.01 to 0.70 and exercise v antiplatelets 0.10, 0.01 to 0.62). Diuretics were more effective than exercise in heart failure (exercise v diuretics 4.11,1.17to 24.76). Inconsistency between direct and indirect comparisons was not significant. Conclusions Although limited in quantity, existing randomised trial evidence on exercise interventions suggests that exercise and many drug interventions are often potentially similar in terms of their mortality benefits in the secondary prevention of coronary heart disease, rehabilitation after stroke, treatment of heart failure, and prevention of diabetes.
