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The Existence of Publication Bias and Risk Factors for Its Occurrence

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Publication bias is the tendency on the parts of investigators, reviewers, and editors to submit or accept manuscripts for publication based on the direction or strength of the study findings. Much of what has been learned about publication bias comes from the social sciences, less from the field of medicine. In medicine, three studies have provided direct evidence for this bias. Prevention of publication bias is important both from the scientific perspective (complete dissemination of knowledge) and from the perspective of those who combine results from a number of similar studies (meta-analysis). If treatment decisions are based on the published literature, then the literature must include all available data that is of acceptable quality. Currently, obtaining information regarding all studies undertaken in a given field is difficult, even impossible. Registration of clinical trials, and perhaps other types of studies, is the direction in which the scientific community should move.
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... 200 R. bras. Ci. e Mov 2020;28(8):194-201.Parafraseando a citação do pesquisadorDickersin (1999) 3 , se o viés de publicação existe, será que é importante se preocupar? Primeiramente vamos relembrar que o viés de publicação acontece quando os resultados da publicação são baseados na direção ou achados significativos 3 . ...
... In turn, many excellent contributions are rejected when the acceptance rate is very low (Miner, 2003). At the same time, peer review is notoriously affected by the so-called "publication bias"; namely, articles presenting positive, large, and surprising effects have higher chances to be published, and in many cases such results are not confirmed by later studies (Dickersin 1990;Fanelli 2012). ...
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This chapter explores the main challenges of peer review in scientific journals, with special attention to our current knowledge and key research gaps on journal peer review in the social sciences. The first part of the chapter examines the efficacy and efficiency of peer review in selecting the most valid and important contributions and in contributing to the improvement of scientific manuscripts, as well as issues of low reliability, bias, and large direct and indirect costs. The second part of the chapter discusses different models of peer review according to the anonymity of authors and reviewers, the pros and cons of post-publication peer review, and the ongoing debate about the need and risks of reforming peer review. The chapter concludes with implications for journal editors and manuscript evaluation.
... Second, all data were extracted from the SCIE of Web of Science, thus, we may fail to capture certain related publications provided in other sources. Third, despite we analyzed the top-cited articles in this field representing the research hotspots, we admit certain research topics with few publications due to publication bias [75], may be missed. In addition, 'obliteration by incorporation' , which represents that the older publications are no longer cited because their findings are common-use and incorporated into the current discipline, is a notable concern in the bibliometric analysis [76]. ...
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Background Chronic kidney disease (CKD) affects 8 to 16% of the world’s population and is one of the top ten important drivers of increasing disease burden. Apart from genetic predisposition, lifestyle factors greatly contribute to the incidence and progression of CKD. The current bibliometric analysis aims to characterize the current focus and emerging trends of the research about the impact of modifiable lifestyle factors on CKD. Methods We searched articles addressing the impact of modifiable lifestyle factors on the incidence and/or progression of CKD, published between 2011 and 2020, from the Science Citation Index Expanded (SCIE) database. An adjusted citation index, which considered both the original citation count and publication year, was derived for the selection of most-cited publications. Publishing trends, co-authorship network, keywords, and research hotspots were analyzed and visualized. Results Among the top 100 most influential articles, 32 were narrative reviews, 16 systematic reviews and/or meta-analysis, 44 clinical research, and 8 basic research. The United States occupied a dominant position in the perspective of article numbers and international partnerships, followed by European countries. The modifiable factors that drew the most and constant attention over the decade were diet or nutrition management reported in 63 papers, followed by obesity or body mass index ( n = 27), and physical activity or exercises ( n = 8). Alcohol consumption, fish oil, chain fatty-acids, and water-soluble vitamins were emerging hotspots identified in the recent most cited publications. Conclusions Based on the bibliometric analysis of the most influential articles, our study provides a comprehensive description of publishing trends and research focus over a decade in the field of lifestyle factors’ impact on CKD. Diet, obesity, and physical activity were factors receiving the most attention in this topic.
... Cette autocensure peut provenir de différentes raisons, d'hypothèses malp osées, d'un manque de participants, d'une anticipation de refus des comitésd el ecture des revues, d'une volonté de ne pas essuyer de critiques d'une communauté de chercheurs, de problèmes de financement. D'autres raisons externes à cette autocensure sont possibles comme par exemple le refus systématique de comitésd el ecture des revues, une stratégie délibéréed es organismes financeurs ou promoteurs de l'étude ou l'habitude du laboratoire de recherche [34]. Quelles qu'en soient les raisons, les travaux non publiésd ans des revues académiques, appelésl al ittérature grise, ont comme conséquence pour les méta-analyses de s'appuyer trop sur les essais positifs et donc de surestimer l'efficacité des solutions de santéé valuées. ...
Article
Le nombre de publications d’études cliniques évaluant les interventions non médicamenteuses (INM) augmente exponentiellement depuis 2000. Il encourage les chercheurs à réaliser les revues systématiques et les méta-analyses attendues par les professionnels de santé, les patients et les décideurs pour connaître leur efficacité réelle et leur indication pertinente. Seulement, la diversification des supports de communication médicale et scientifique, les stratégies opportunistes de publication, les informations manquantes dans les publications et la non exhaustivité des bases de données biomédicales rendent la recherche bibliographique complexe et à risque de biais. Pour répondre à ce manque, la Plateforme CEPS propose un moteur de recherche, appelé Motrial, qui permet de collecter, de trier et d’organiser les publications d’études cliniques sur les INM.
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ClinicalTrials.gov is a federally supported, web-based clinical trials registry maintained by the United States (US) National Library of Medicine (NLM) at the National Institutes of Health (NIH). It is available to health care professionals, researchers, patients, and the public. Since its launch in 2000, over 325,000 clinical research studies have been registered in ClinicalTrials.gov. Unlike other clinical trial registries and databases, clinical trials registration for certain types of clinical trials is mandated by law under Section 801 of the US Food and Drug Administration Amendments Act (FDAAA 801). There are several components that make up the ClinicalTrials.gov registration process, including trial registration itself, results reporting, and the download and analysis of the ClinicalTrials.gov content. While the previous chapter focuses on clinical trials registration in general, this chapter pertains to clinical trials registered in ClinicalTrials.gov. This chapter provides an overview of the history of ClinicalTrials.gov, a description of the trials currently registered in ClinicalTrials.gov, and a review of the Federal Requirements for Registration in the United States. A summary of the registration process, trial reporting, and data analysis procedures follows. The chapter concludes with an overview of the limitations associated with the analysis and reporting of ClinicalTrials.gov registration data.
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A p value, or the magnitude or direction of results, can influence decisions about whether, when, and how research findings are disseminated. Regardless of whether an entire study or a particular study result is unavailable because investigators considered the results to be unfavorable, reporting bias in a meta‐analysis may occur when available results differ systematically from missing results. This reinforces the need for review authors to search or consult multiple sources that include bibliographic databases, trials registers, manufacturers, regulators, and study authors or sponsors where or through whom study reports and results may be located. Unless prospective approaches to meta‐analysis can eliminate the potential for bias due to missing results, review authors should formally assess the risk of bias in their review. Several approaches can facilitate such assessment: tools to record selective reporting of results, ascertaining qualitative signals that suggest not all studies were identified, and the use of funnel plots to identify small‐study effects, one cause of which is reporting bias.
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The past 30 years of genetic analysis have helped to confirm theories, conceived at the beginning of the twentieth century, that complex diseases are heritable and likely to be influenced by many genetic factors, each exhibiting small effects. Detecting these genetic factors could be valuable for developing new drugs or predicting adverse outcomes before onset, but detection is generally only possible when the sample sizes are very large. We describe the failures in genetic analyses that have brought us to this understanding, and led to the development of the genome‐wide association study (GWAS) framework. Meta‐analysis has played a central role in GWAS and has helped to yield tens of thousands of genetic associations for a wide range of complex traits and diseases. We discuss how meta‐analysis is implemented in the GWAS context, noting the technical challenges that arise and the various contexts in which it can be applied.
Article
OBJETIVO: evaluar si los estudios publicados en revistas académicas arbitradas de recién creación en México y Guatemala se pueden reproducir. Asimismo, se pretendió evaluar si se hacen replicaciones de estudios. De igual forma, si están presentes prácticas de investigación cuestionables y sesgo de publicación. MÉTODO: en este estudio se usó un diseño cuantitativo, descriptivo y transversal. Se obtuvo una muestra de conveniencia de 20 estudios de México y 10 de Guatemala, uno por revista creada en el 2021. RESULTADOS: se encontró que ninguno de los estudios se puede reproducir. Asimismo, hay una ausencia de replicaciones en las investigaciones. Se descubrió que pocos estudios presentaban prácticas de investigación cuestionables. Asimismo, no se observó sesgo de publicación en las investigaciones. CONCLUSIÓN: se concluyó que la reproducibilidad y replicación de estudios no son populares en revistas académicas arbitradas de recién creación de este estudio. Despierta gran preocupación que los resultados no se puedan verificar. Asimismo, es preocupante que no haya replicación de estudios en revistas de recién creación. Estas problemáticas deben ser abordadas por los entes editoriales a la brevedad.
Article
OBJETIVO: evaluar si las tesis de maestría y doctorado en repositorios de tesis de acceso abierto en México y Guatemala se pueden reproducir. Asimismo, se pretendió evaluar si se hacen replicaciones de estudios. De igual forma, si están presentes prácticas de investigación cuestionables y sesgo de publicación. MÉTODO: en este estudio se usó un diseño cuantitativo, descriptivo y transversal. Se obtuvo una muestra de conveniencia de 17 estudios de 13 repositorios institucionales de México y 8 estudios de 6 repositorios de Guatemala. El universo consistió en 46 repositorios institucionales de México (enlistados en la Red Mexicana de Repositorios Institucionales) y 7 de Guatemala. RESULTADOS: se encontró que ninguno de los estudios se puede reproducir. Asimismo, hay una ausencia de replicaciones en las investigaciones. Se descubrió que la mayoría de las investigaciones presentaba prácticas de investigación cuestionables. Sin embargo, no se observó sesgo de publicación en los estudios. CONCLUSIÓN: se concluyó que la reproducibilidad y replicación de estudios no son populares en las universidades que formaron parte de este estudio. Asimismo, despierta gran preocupación observar prácticas de investigación cuestionables en la mayoría de las investigaciones de este estudio. Las universidades deben abordar estas problemáticas a la brevedad.
Article
Substantial numbers of clinical trials continue to be reported only in summary reports that present insufficient methodological details to permit informed judgments about the likely validity of the conclusions. Using a cohort of 176 controlled trials reported in summary form, we tested the hypotheses that they would be more likely to be followed by full reports if, on the basis of the information provided in the summary report, (1) the trial was judged to be methodologically sound, (2) the results favored the test treatment, and (3) the sample size was relatively large. The results of univariate and multivariate analyses provided support for only the third of these hypotheses. Investigators, as well as those who fund and sanction the conduct of clinical research, should make greater efforts to ensure that clinical trials are reported properly. (JAMA. 1990;263:1401-1405)
Article
The Physician Data Query (PDQ) system is a clinically oriented computer data base developed to make recent information on cancer treatment widely available to the medical community. It represents an effort by the National Cancer Institute to promote diffusion of information about the treatment of cancer throughout the country, facilitate access to clinical trials, and accelerate the practical application of advances in research. The computer system provides information about state-of-the-art cancer treatment, which is updated monthly by an editorial board. It also includes a file of active cancer-research protocols and a directory of physicians and organizations providing cancer care to which physicians can gain access by geographic location as well as other features. PDQ was designed for physicians who may not be familiar with computers, to permit them to search for and display information without learning a specialized search language. PDQ uses a computer mainframe, which allows a large amount of data to be stored and made available to physicians rapidly and accurately. Transmission of information about cancer over commercial telecommunication networks gives health professionals access to PDQ by means of a computer terminal and local telephone lines.
Article
Publication bias, the phenomenon in which studies with positive results are more likely to be published than studies with negative results, is a serious problem in the interpretation of scientific research. Various hypothetical models have been studied which clarify the potential for bias and highlight characteristics which make a study especially susceptible to bias. Empirical investigations have supported the hypothesis that bias exists and have provided a quantitative assessment of the magnitude of the problem. The use of meta-analysis as a research tool has focused attention on the issue, since naive methodologies in this area are especially susceptible to bias. In this paper we review the available research, discuss alternative suggestions for conducting unbiased meta-analysis and suggest some scientific policy measures which could improve the quality of published data in the long term.
Article
There has been much speculation but little data about the number of unpublished studies located in “file drawers.” If the number is high, and if those studies yield systematically different effects, then literature reviews that ignore them might yield biased results. As part of an ongoing meta-analysis of the effectiveness of marital/family therapies, the authors asked 519 randomly sampled members of five relevant organizations if they had file drawer studies. A total of 375 respondents yielded three such unpublished studies that would otherwise have qualified for inclusion in the meta-analysis. Resulting population estimates suggest that there may be almost as many family/marital psychotherapy studies in the file drawer as there are published studies and dissertations. However, because so few file drawer studies were actually obtained, very large confidence intervals surrounded the estimate of the magnitude of effect sizes. Hence the degree of bias resulting from the file drawer problem is still in doubt. Available evidence in this and other studies suggests that the conservative conclusion is to assume that population effect sizes are only 70–90% as large as those computed from published studies.
Article
The file drawer problem refers to a publication bias for positive results, leading to studies which support the null hypothesis being relegated to the file drawer. The assumption is that researchers are unable to publish studies with nonsignificant findings. A survey of investigators studying the menstrual cycle showed this assumption to be unwarranted. Much of the research did not lend itself to a hypothesis-testing model. A more important contribution to the likelihood of publication was research productivity, and researchers whose first study was published were more likely to have continued their work.
Article
The purposes of this study were to determine the proportion of papers which contain negative results (results which fail to reject the null hypothesis), and whether there is some selection in the papers published such that negative results are unlikely to be published. An examination of current psychological journals indicated that studies with negative results constitute about 9 per cent of the total volume of published papers. However, data from several unpublished sources indicate that negative results are less likely to be published. The reasons for their neglect - chiefly author selection and the greater editorial scrutiny they get - were presented. The practical, statistical and heuristic value of negative results was also discussed.
Article
The potential magnitude of publication bias has been examined with a consecutive sample of published cancer clinical trials. The analysis is based on the premise that the magnitude of the true treatment effect is unrelated to design features of the study, in particular sample size. This assumption permits an analysis based only on published studies. Three primary endpoints are examined: overall patient survival, disease-free survival, and tumor response rate. There are striking trends for each endpoint, with small studies appearing to possess large treatment effects and large studies possessing relatively small effects. It is believed that these differences are primarily due to publication bias. The bias is very large: Absolute differences observed were 41% for overall survival, 79% for disease-free survival, and 17% for response rates. Other study features have been examined that might be associated with bias, or that might be responsible for the striking trends regarding sample size. The results indicate that absence of randomization leads to significant bias, and studies conducted in a single institution are somewhat more prone to bias than multiinstitutional studies, though the trends are less consistent in the latter case. No strong trend was observed for journal type. Nevertheless, none of these variables could account for the strong effect of sample size. Sensitivity analyses of the results were conducted and alternative models were considered. These analyses generally support the contention that the magnitude of the bias due to sample size cannot be explained by alternative factors. An implication of this study is that the results of small published studies are typically unreliable, even taking into account the fact that such trials are imprecise due to sampling variation.