Umbrella reviews: what they are and why we need them

Preferred Reporting Items for Systematic Reviews and Meta-Analyses: the PRISMA statement

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Bias in meta-analysis detected by a simple, graphical test

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Preferred reporting items for systematic reviews and meta-analyses: the PRISMA Statement.

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The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration

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Operating characteristics of a rank correlation test for publication bias

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Evidence based medicine: what it is and what it isn't

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GRADE guidelines: 1. Introduction—GRADE evidence profiles and summary of findings tables

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AMSTAR 2: a critical appraisal tool for systematic reviews that include randomised or non-randomised studies of healthcare interventions, or both.

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GRADE guidelines: 3. Rating the quality of evidence

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A basic introduction to fixed-effect and random-effects models for meta-analysis

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Improving the quality of reports of meta-analyses of randomised controlled trials: the QUOROM statement

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MESSAGE FROM THE EDITOR

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GRADE guidelines: a new series of articles in the Journal of Clinical Epidemiology

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Redefine statistical significance

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Plea for routinely presenting prediction intervals in meta-analysis.

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Systematic Reviews: Identifying relevant studies for systematic reviews

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AMSTAR is a reliable and valid measurement tool to assess the methodological quality of systematic reviews

Shea, B. J., Hamel, C., Wells, G. A., Bouter, L. M., Kristjansson, E., Grimshaw, J., Henry, D. A., & Boers, M. (2009) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2008.10.009 · Cited by 1,755

The Mass Production of Redundant, Misleading, and Conflicted Systematic Reviews and Meta‐analyses

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Evidence summaries: the evolution of a rapid review approach

Khangura, S., Konnyu, K., Cushman, R., Grimshaw, J., & Moher, D. (2012) · Systematic Reviews · doi:10.1186/2046-4053-1-10 · Cited by 1,232

Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational studies and randomised trials

Theodoratou, E., Tzoulaki, I., Zgaga, L., & Ioannidis, J. P. A. (2014) · BMJ · doi:10.1136/bmj.g2035 · Cited by 956

Type 2 diabetes and cancer: umbrella review of meta-analyses of observational studies

Tsilidis, K. K., Kasimis, J. C., López, D. S., Ntzani, E., & Ioannidis, J. P. A. (2015) · BMJ · doi:10.1136/bmj.g7607 · Cited by 885

The GRADE Working Group clarifies the construct of certainty of evidence

Hultcrantz, M., Rind, D., Akl, E. A., Treweek, S., Mustafa, R. A., Iorio, A., Alper, B. S., Meerpohl, J. J., Murad, M. H., Ansari, M. T., et al. (2017) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2017.05.006 · Cited by 853

Coffee consumption and health: umbrella review of meta-analyses of multiple health outcomes

Poole, R., Kennedy, O. J., Roderick, P., Fallowfield, J. A., Hayes, P. C., & Parkes, J. (2017) · BMJ · doi:10.1136/bmj.j5024 · Cited by 835

Validation of an index of the quality of review articles

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An exploratory test for an excess of significant findings

Ioannidis, J. P., & Trikalinos, T. A. (2007) · Clinical Trials · doi:10.1177/1740774507079441 · Cited by 751

Integration of evidence from multiple meta-analyses: a primer on umbrella reviews, treatment networks and multiple treatments meta-analyses

Ioannidis, J. P. A. (2009) · Canadian Medical Association Journal · doi:10.1503/cmaj.081086 · Cited by 716

Environmental risk factors and multiple sclerosis: an umbrella review of systematic reviews and meta-analyses

Belbasis, L., Bellou, V., Εvangelou, Ε., Ioannidis, J. P. A., & Tzoulaki, I. (2015) · The Lancet Neurology · doi:10.1016/s1474-4422(14)70267-4 · Cited by 715

Statistical methods for assessing the influence of study characteristics on treatment effects in 'meta-epidemiological' research

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Mapping risk factors for depression across the lifespan: An umbrella review of evidence from meta-analyses and Mendelian randomization studies

Köhler, C. A., Evangelou, E., Stubbs, B., Solmi, M., Veronese, N., Belbasis, L., Bortolato, B., Melo, M. C. A., Coelho, C. A., Fernandes, B. S., et al. (2018) · Journal of Psychiatric Research · doi:10.1016/j.jpsychires.2018.05.020 · Cited by 302

Excess Significance Bias in the Literature on Brain Volume Abnormalities

Ioannidis, J. P. A. (2011) · Archives of General Psychiatry · doi:10.1001/archgenpsychiatry.2011.28 · Cited by 299

Systematic evaluation of the associations between environmental risk factors and dementia: An umbrella review of systematic reviews and meta‐analyses

Bellou, V., Belbasis, L., Tzoulaki, I., Middleton, L. T., Ioannidis, J. P. A., & Εvangelou, Ε. (2016) · Alzheimer s & Dementia · doi:10.1016/j.jalz.2016.07.152 · Cited by 298

The association of depression and all-cause and cause-specific mortality: an umbrella review of systematic reviews and meta-analyses

Machado, M. O., Veronese, N., Sanches, M., Stubbs, B., Koyanagi, A., Thompson, T., Tzoulaki, I., Solmi, M., Vancampfort, D., Schuch, F. B., et al. (2018) · BMC Medicine · doi:10.1186/s12916-018-1101-z · Cited by 281

A descriptive analysis of overviews of reviews published between 2000 and 2011.

Hartling, L., Chisholm, A., Thomson, D., & Dryden, D. M. (2012) · PLoS ONE · doi:10.1371/journal.pone.0049667 · Cited by 241

Genetic and non‐genetic risk factors for pre‐eclampsia: umbrella review of systematic reviews and meta‐analyses of observational studies

Giannakou, K., Εvangelou, Ε., & Papatheodorou, S. (2017) · Ultrasound in Obstetrics and Gynecology · doi:10.1002/uog.18959 · Cited by 209

Publishing Protocols of Systematic Reviews: Comparing What Was Done to What Was Planned

Silagy, C. A., Middleton, P., & Hopewell, S. (2002) · JAMA · doi:10.1001/jama.287.21.2831 · Cited by 188

Using data sources beyond PubMed has a modest impact on the results of systematic reviews of therapeutic interventions

Halladay, C. W., Trikalinos, T. A., Schmid, I. T., Schmid, C. H., & Dahabreh, I. J. (2015) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2014.12.017 · Cited by 166

Synthesis of observational studies should consider credibility ceilings

Salanti, G., & Ioannidis, J. P. A. (2009) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2008.05.014 · Cited by 108

Enhanced recovery after elective caesarean: a rapid review of clinical protocols, and an umbrella review of systematic reviews

Corso, E., Hind, D., Beever, D., Fuller, G., Wilson, M. J. A., Wrench, I., & Chambers, D. (2017) · BMC Pregnancy and Childbirth · doi:10.1186/s12884-017-1265-0 · Cited by 94

Evaluation of Excess Statistical Significance in Meta-analyses of 98 Biomarker Associations with Cancer Risk

Tsilidis, K. K., Papatheodorou, S., Εvangelou, Ε., & Ioannidis, J. P. A. (2012) · JNCI Journal of the National Cancer Institute · doi:10.1093/jnci/djs437 · Cited by 92

Improving the use of research evidence in guideline development: 16. Evaluation

Oxman, A. D., Schünemann, H. J., & Fretheim, A. (2006) · Health Research Policy and Systems · doi:10.1186/1478-4505-4-28 · Cited by 73

The role of meta-analyses and umbrella reviews in assessing the harms of psychotropic medications: beyond qualitative synthesis.

Solmi, M., Correll, C. U., Carvalho, A. F., & Ioannidis, J. P. A. (2018) · Epidemiology and Psychiatric Sciences · doi:10.1017/s204579601800032x · Cited by 44

Efficacy, tolerability, and safety of non-pharmacological therapies for chronic pain: An umbrella review on various CAM approaches

Houzé, B., El-Khatib, H., & Arbour, C. (2017) · Progress in Neuro-Psychopharmacology and Biological Psychiatry · doi:10.1016/j.pnpbp.2017.06.035 · Cited by 22

Reprint of: Efficacy, tolerability, and safety of non-pharmacological therapies for chronic pain: An umbrella review on various CAM approaches

Houzé, B., El-Khatib, H., & Arbour, C. (2018) · Progress in Neuro-Psychopharmacology and Biological Psychiatry · doi:10.1016/j.pnpbp.2018.08.002 · Cited by 17

A simple method for converting an odds ratio to effect size for use in meta-analysis

Chinn, S. (2000) · Statistics in Medicine · doi:10.1002/1097-0258(20001130)19:22

Objectives, design and main findings until 2020 from the Rotterdam Study

Ikram, M. A., Brusselle, G., Ghanbari, M., Goedegebure, A., Ikram, M. K., Kavousi, M., Kieboom, B. C. T., Klaver, C. C. W., de Knegt, R. J., Luik, A. I., et al. (2020) · European Journal of Epidemiology · doi:10.1007/s10654-020-00640-5 · Cited by 463

Association between Adiposity and Cardiovascular Outcomes: An Umbrella Review and Meta-Analysis

Kim, M. S., Kim, W. J., Khera, A. V., Kim, J. Y., Yon, D. K., Lee, S. W., Shin, J. I., & Won, H. (2020) · European Heart Journal · doi:10.1093/eurheartj/ehab454 · Cited by 400

Efficacy of Psychosocial Interventions for Mental Health Outcomes in Low-Income and Middle-Income Countries: An Umbrella Review

Barbui, C., Purgato, M., Abdulmalik, J., Acarturk, C., Eaton, J., Gastaldon, C., Gureje, O., Hanlon, C., Jordans, M., Lund, C., et al. (2020) · The Lancet Psychiatry · doi:10.1016/s2215-0366(19)30511-5 · Cited by 349

Dietary sugar consumption and health: umbrella review

Huang, Y., Chen, Z., Chen, B., Li, J., Yuan, X., Li, J., Wang, W., Dai, T., Chen, H., Wang, Y., et al. (2023) · BMJ · doi:10.1136/bmj-2022-071609 · Cited by 348

Tomato and lycopene and multiple health outcomes: Umbrella review

Li, N., Wu, X., Zhuang, W., Xia, L., Chen, Y., Wu, C., Rao, Z., Du, L., Zhao, R., Yi, M., et al. (2020) · Food Chemistry · doi:10.1016/j.foodchem.2020.128396 · Cited by 267

A critical reflection on the grading of the certainty of evidence in umbrella reviews

Schlesinger, S., Schwingshackl, L., Neuenschwander, M., & Barbaresko, J. (2019) · European Journal of Epidemiology · doi:10.1007/s10654-019-00531-4 · Cited by 31

Author Reply: A critical reflection on the grading of the certainty of evidence in umbrella reviews

Papatheodorou, S. (2019) · European Journal of Epidemiology · doi:10.1007/s10654-019-00535-0 · Cited by 1

Umbrellas Dangerous.

(1869) · PubMed Central

Building a better umbrella.

Styles, M. M. (1987) · PubMed

An umbrella--or a crutch.

Lux, B. (1969) · PubMed