Abstract
In systematic reviews and meta-analyses, publication bias is particularly problematic, given that combining only statistically significant outcomes is likely to overestimate the true effect of an intervention since non-significant findings have been omitted. We examined practices for evaluating publication bias from gastroenterology literature. We performed a PubMed search to identify systematic reviews published in American Journal of Gastroenterology, Gut, and Gastroenterology from 2005 to 2015. Of the 304 found, 215 studies were eligible for inclusion based on relevant study characteristics. There were 190 systematic reviews which used at least one method to evaluate publication bias and/or included ten or more primary studies. There were 115/190 (60.53%) systematic reviews which used at least one method to evaluate publication bias. Most (105/115, 91.27%) qualified reviews used at least one method to evaluate publication bias and 78/115 (67.83%) used a combination of methods. The most common methods were funnel plot (100/115, 86.96%), Egger’s regression (67/115, 58.26%), and Begg’s (28/115, 24.35%). Of the 115 reviews that performed evaluations, 26 (22.61%) conducted these analyses with fewer than ten primary studies, and a minority (24/115, 20.87%) reached the conclusion that publication bias was present in their work. While methods to assess publication bias were frequently noted among qualified systematic reviews, these methods are limited in value and could be improved by incorporating approaches that assess the degree of publication bias severity.
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References
Nikolaos A, Patsopoulos MD, Apostolos AA, et al. Relative citation impact of various study designs in the health sciences. JAMA. 2005;293:2362–6.
Sutton AJ. Evidence concerning the consequences of publication and related biases. In: Rothstein HR, Sutton AJ, Borenstein M, eds. Publication Bias in Meta-Analysis-Prevention, Assessment and Adjustments. Chichester: John Wiley & Sons; 2005.
Kepes S, Banks G, McDaniel M, et al. Publication bias in the organizational sciences. Organ Res Methods. 2012;15:624–62.
Dickersin K. The existence of publication bias and risk factors for its occurrence. JAMA. 1990;263:1385–9.
Song F, Parekh S, Hooper L, et al. Dissemination and publication of research findings: an updated review of related biases. Health Technol Assess. 2010;14:1–193.
Moreno SG, Sutton AJ, Ades AE, et al. Assessment of regression-based methods to adjust for publication bias through a comprehensive simulation study. BMC Med Res Methodol. 2009;9:2.
Terrin N, Schmid CH, Lau J, Olkin I. Adjusting for publication bias in the presence of heterogeneity. Stat Med. 2003;22:2113–26.
Higgins JPT, Green S, eds. Cochrane Handbook for Systematic Reviews of Interventions. The Cochrane Collaboration, 2011.
van Enst WA, Ochodo E, Scholten RJ, Hooft L, Leeflang MM. Investigation of publication bias in meta-analyses of diagnostic test accuracy: a meta-epidemiological study. BMC Med Res Methodol. 2014;14:70.
Sterne JA, Sutton AJ, Ioannidis JP, et al. Recommendations for examining and interpreting funnel plot asymmetry in meta-analyses of randomised controlled trials. BMJ. 2011;343:d4002.
Moher D, Tetzlaff J, Tricco AC, Sampson M, Altman DG. Epidemiology and reporting characteristics of systematic reviews. PLoS Med. 2007;4:e78.
Onishi A, Furukawa TA. Publication bias is underreported in systematic reviews published in high-impact-factor journals: metaepidemiologic study. J Clin Epidemiol. 2014;67:1320–6.
Atakpo P, Vassar M. Publication bias in dermatology systematic reviews and meta-analyses. J Dermatol Sci. 2016;82:69–74.
Hedin RJ, Umberham BA, Detweiler BN, Kollmorgen L, Vassar M. Publication bias and nonreporting found in majority of systematic reviews and meta-analyses in anesthesiology journals. Anesth Analg. 2016;123:1018–25.
Montori VM, Wilczynski NL, Morgan D. Optimal search strategies for retrieving systematic reviews from Medline: analytical survey. BMJ. 2005;330:68–0.
Haynes RB, Cotoi C, Holland J, et al. Second-order peer review of the medical literature for clinical practitioners. JAMA. 2006;19:1801–8.
Garg AX, Hackam D, Marcello T. Systematic review and meta-analysis: when one study is just not enough. Clin J Am Soc Nephrol. 2008;3:253–60.
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TH, and MV declare that they have no conflict of interest.
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This study did not utilize animal or human subjects and was approved by the Oklahoma State University Center for Health Sciences Institutional Review Board.
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Appendix
Appendix
Number of studies | Method(s) used |
---|---|
51 | Funnel, Egger |
28 | Funnel |
8 | Funnel, Begg, Egger |
5 | Funnel, Begg, and Mazumdar |
5 | Egger |
4 | Begg, Egger |
3 | Funnel, Begg |
2 | Begg |
1 | Begg and Mazumdar, Egger |
1 | Begg, Harbord |
1 | Funnel, Begg and Mazumdar, trim-and-fill |
1 | Funnel, Begg, Egger, trim-and-fill |
1 | Funnel, Begg, trim-and-fill |
1 | Funnel, Egger, Begg, trim-and-fill, Kendall’ s tau |
1 | Funnel, Egger, trim-and-fill |
1 | Klein method |
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Heavener, T., Vassar, M. A review of publication bias in the gastroenterology literature. Indian J Gastroenterol 37, 58–62 (2018). https://doi.org/10.1007/s12664-018-0824-2
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DOI: https://doi.org/10.1007/s12664-018-0824-2