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Cited by 3,994Meta-analysis and systematic reviewsGenetic Associations and EpidemiologyStatistical Methods in Epidemiology

Strengthening the Reporting of Observational Studies in Epidemiology Using Mendelian Randomization: The STROBE-MR Statement

Open access
Skrivankova, Veronika W., Richmond, Rebecca C., Woolf, Benjamin A. R., Yarmolinsky, James, Davies, Neil M., Swanson, Sonja A., VanderWeele, Tyler J., Higgins, Julian P. T. +10 more·2021·JAMA
DOI 10.1001/jama.2021.18236
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Abstract

Importance: Mendelian randomization (MR) studies use genetic variation associated with modifiable exposures to assess their possible causal relationship with outcomes and aim to reduce potential bias from confounding and reverse causation. Objective: To develop the STROBE-MR Statement as a stand-alone extension to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guideline for the reporting of MR studies. Design, Setting, and Participants: The development of the STROBE-MR Statement followed the Enhancing the Quality and Transparency of Health Research (EQUATOR) framework guidance and used the STROBE Statement as a starting point to draft a checklist tailored to MR studies. The project was initiated in 2018 by reviewing the literature on the reporting of instrumental variable and MR studies. A group of 17 experts, including MR methodologists, MR study design users, developers of previous reporting guidelines, and journal editors, participated in a workshop in May 2019 to define the scope of the Statement and draft the checklist. The draft checklist was published as a preprint in July 2019 and discussed on the preprint platform, in social media, and at the 4th Mendelian Randomization Conference. The checklist was then revised based on comments, further refined through 2020, and finalized in July 2021. Findings: The STROBE-MR checklist is organized into 6 sections (Title and Abstract, Introduction, Methods, Results, Discussion, and Other Information) and includes 20 main items and 30 subitems. It covers both 1-sample and 2-sample MR studies that assess 1 or multiple exposures and outcomes, and addresses MR studies that follow a genome-wide association study and are reported in the same article. The checklist asks authors to justify why MR is a helpful method to address the study question and state prespecified causal hypotheses. The measurement, quality, and selection of genetic variants must be described and attempts to assess validity of MR-specific assumptions should be well reported. An item on data sharing includes reporting when the data and statistical code required to replicate the analyses can be accessed. Conclusions and Relevance: STROBE-MR provides guidelines for reporting MR studies. Improved reporting of these studies could facilitate their evaluation by editors, peer reviewers, researchers, clinicians, and other readers, and enhance the interpretation of their results.

AI snapshot

Written from the paper’s full text.

TL;DR

The STROBE-MR Statement is a reporting guideline for Mendelian randomization (MR) studies, developed as a stand-alone extension of STROBE using EQUATOR guidance. It provides a 20-item, 30-subitem checklist covering 1-sample and 2-sample MR studies and emphasizes transparent reporting of MR-specific assumptions, validity assessments, and data/code availability.

Key findings

  • The final STROBE-MR checklist is organized into 6 sections (Title and Abstract, Introduction, Methods, Results, Discussion, and Other Information) and includes 20 main items and 30 subitems.
  • It covers both 1-sample and 2-sample MR studies assessing one or multiple exposures and outcomes, including MR studies that follow a genome-wide association study and are reported in the same article.
  • Pilot testing on 20 MR articles published in 2018 found reporting deficiencies: none of the 10 2-sample MR studies described the underlying exposure and outcome study populations in detail, compared them, or discussed sample overlap; only 10 studies (50%) reported efforts to test and correct for possible pleiotropy; details on imputation of missing genetic data or minor allele frequency cutoffs were missing in 11 of 20 articles (55%); instrument strength was reported in 10 (50%); 10 (50%) lacked discussion of clinical or public health relevance; and 13 (65%) did not address generalizability.
  • The checklist asks authors to justify why MR is helpful, state prespecified causal hypotheses, describe measurement/quality/selection of genetic variants, report assessment of MR assumptions, and report where data and statistical code can be accessed.

Methods

  • Development followed the EQUATOR framework, used STROBE as a starting point, and was initiated in 2018 by reviewing literature on reporting of instrumental variable and MR studies.
  • A group of 17 experts participated in a May 2019 workshop; the draft checklist was published as a preprint in July 2019, revised through 2020, and finalized in July 2021.
  • The draft checklist was pilot-tested on a random sample of 20 original MR articles published in 2018 (10 one-sample and 10 two-sample), selected from 404 potentially eligible articles as of April 1, 2019; this was not intended as a systematic review.

Limitations

  • The paper states that the statement does not describe all methods that can be used to assess all assumptions required in an MR study, although major assumptions and commonly used methods are described.
  • The paper states that, as a consensus document, it will be updated with further community feedback, and that no systematic review was undertaken to better understand reporting deficiencies in MR studies.
  • Evident from the text: no formal Delphi process was performed, the pilot review was not a systematic review, and the checklist is explicitly not intended as an instrument to evaluate MR research quality.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1001/jama.2021.18236

Cites

30 of 30 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 10 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Information on the strength of genetic instrument was reported in 10 (50%) of the 20 studies.

    “Information on the strength of genetic instrument was reported in 10 (50%) of the 20 studies.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The 20 randomly selected 2018 Mendelian randomization articles are representative enough to confirm reporting deficiencies in Mendelian randomization studies.
  • Findingown data

    None of the 10 2-sample Mendelian randomization studies described the underlying exposure and outcome study populations in detail, compared them, or discussed sample overlap.

    “For example, none of the 10 2-sample mendelian randomization studies described the underlying exposure and outcome study populations in detail, compared them, or discussed sample overlap.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The 20 randomly selected 2018 Mendelian randomization articles are representative enough to confirm reporting deficiencies in Mendelian randomization studies.
  • Findingown data

    Only 10 studies (50%) reported efforts to test and correct for possible pleiotropy.

    “Only 10 studies (50%) reported efforts to test and correct for possible pleiotropy.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The 20 randomly selected 2018 Mendelian randomization articles are representative enough to confirm reporting deficiencies in Mendelian randomization studies.
  • Findingown data

    Details on the imputation of missing genetic data or minor allele frequency cutoffs were missing in 11 of the 20 articles reviewed (55%).

    “Details on the imputation of missing genetic data or minor allele frequency cutoffs were missing in 11 of the 20 articles reviewed (55%).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The 20 randomly selected 2018 Mendelian randomization articles are representative enough to confirm reporting deficiencies in Mendelian randomization studies.
  • Findingown data

    13 (65%) of the surveyed publications did not address the generalizability of the study results.

    “Ten (50%) of the surveyed publications lacked a discussion of clinical or public health relevance, and 13 (65%) did not address the generalizability of the study results.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The 20 randomly selected 2018 Mendelian randomization articles are representative enough to confirm reporting deficiencies in Mendelian randomization studies.
  • Classified as probably not a substantial claim. 33
  • May combine two claims. 17

  • Classified as probably not a substantial claim.

    Findingreasoning

    All other items and subitems were modified to address requirements specific to reporting of Mendelian randomization studies.

    “All other items and subitems were modified to address requirements specific to reporting of mendelian randomization studies.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingcitation

    As of July 2021, the preprint had been viewed more than 5000 times and downloaded more than 3500 times.

    “As of July 2021, the preprint had been viewed more than 5000 times and downloaded more than 3500 times.18”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Findingreasoning

    STROBE-MR was developed as a guideline for reporting Mendelian randomization studies.

    “STROBE-MR was developed as a guideline for reporting mendelian randomization studies.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Findingnone given

    STROBE-MR gives much emphasis on the transparent reporting of assessments of the validity of the assumptions and sensitivity analyses to assess the robustness of the main results to violations of the assumptions.

    “STROBE-MR gives much emphasis on the transparent reporting of assessments of the validity of the assumptions and sensitivity analyses to assess the robustness of the main results to violations of the assumptions.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingnone given

    Compared with the original STROBE checklist, which included 22 items and 18 subitems, STROBE-MR has 2 fewer items (20) but 12 more subitems (30).

    “Compared with the original STROBE checklist, 13 which included 22 items and 18 subitems, STROBE-MR has 2 fewer items (20) but 12 more subitems (30).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingcitation

    The STROBE-MR items are grouped into sections Title and Abstract (item 1), Introduction (items 2-3), Methods (items 4-9), Results (items 10-13), Discussion (items 14-17), and Other Information (items 18-20).

    “Similar to the STROBE checklist, 13 the items are grouped into sections Title and Abstract (item 1), Introduction (items 2-3), Methods (items 4-9), Results (items 10-13), Discussion (items 14-17), and Other Information (items 18-20).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Findingnone given

    The STROBE-MR guidelines cover both 1-sample and 2-sample Mendelian randomization studies that assess 1 or multiple exposures and outcomes and Mendelian randomization studies that follow a genome-wide association study and are reported in the same article.

    “They cover both 1-sample and 2-sample mendelian randomization studies that assess or multiple exposures and outcomes and mendelian randomization studies that follow a genome-wide association study and are reported in the same article.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingcitation

    The STROBE-MR guidelines do not apply to genome-wide association studies, sequencing studies, expression studies, or traditional observational epidemiology studies.

    “The STROBE-MR guidelines do not apply to genome-wide association studies, which are covered by STREGA 22 (Strengthening the Reporting of Genetic Association Studies), sequencing studies, expression studies, or the traditional observational epidemiology studies covered by STROBE.13”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingnone given

    Only 1 subitem (No. 6d) remained unchanged.

    “Only 1 subitem (No. 6d) remained unchanged (Table 2).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Findingreasoning

    The STROBE-MR guidelines apply to studies that use properties of germline genetic variation to strengthen potential causal inference of modifiable exposures on outcomes.

    “The group agreed that the guidelines should apply to studies that use properties of germline genetic variation to strengthen potential causal inference of modifiable exposures on outcomes.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Findingnone given

    The STROBE-MR guidelines are tailored to the majority of such studies that use an instrumental variable framework.

    “The guidelines are tailored to the majority of such studies that use an instrumental variable framework.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Mendelian randomization rests on three main assumptions: the genetic variant is associated with the risk factor; the genetic variant is not associated with confounders; and the genetic variant influences the outcome only through the risk factor.

    “As noted by Emdin et al, 2 “[m]endelian randomization rests on 3 main assumptions: (1) the genetic variant is associated with the risk factor; (2) the genetic variant is not associated with confounders; and (3) the genetic variant influences the outcome only through the risk factor.””
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Emdin et al, 2

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Despite increasing relevance and popularity of Mendelian randomization studies, their reporting is often incomplete, which may limit the credibility of potential causal inference.

    “Despite increasing relevance and popularity of mendelian randomization studies, their reporting is often incomplete, which may limit the credibility of potential causal inference.[10][11][12]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [10][11][12]

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisenone given

    Assumptions are violated if there is horizontal pleiotropy, in which the genetic variant influences the outcome independently of the risk factor.

    “Assumptions are violated if, for example, there is horizontal pleiotropy, in which the genetic variant influences the outcome independently of the risk factor.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisereasoning

    Misleading inferences can be generated in Mendelian randomization analyses if the relationships relating the exposure to the outcome are misspecified, for example, if the genotype directly affects the outcome, which then affects the putative exposure (reverse causation).

    “Misleading inferences can be generated in mendelian randomization analyses if the relationships relating the exposure to the outcome are misspecified, for example, if the genotype directly affects the outcome, which then affects the putative exposure (ie, reverse causation).”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Mendelian randomization studies use genetic variation associated with modifiable exposures to assess their possible causal relationship with outcomes and aim to reduce potential bias from confounding and reverse causation.

    “Mendelian randomization (MR) studies use genetic variation associated with modifiable exposures to assess their possible causal relationship with outcomes and aim to reduce potential bias from confounding and reverse causation.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1][2][3]

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Premisenone given

    Mendelian randomization can be applied within the instrumental variable framework if specific assumptions are met.

    “Mendelian randomization can be applied within the instrumental variable framework, if specific assumptions are met.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Systematic reviews of reporting quality in Mendelian randomization studies indicate that many reports do not clearly state or examine the various assumptions of Mendelian randomization methods and report insufficient details on the data sources.

    “Systematic reviews of reporting quality in mendelian randomization studies indicate that many reports of mendelian randomization studies do not clearly state or examine the various assumptions of mendelian randomization methods and report insufficient details on the data sources.[10][11][12]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [10][11][12]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Reporting guidelines are not recommendations for designing or conducting studies, although they may contribute to improving methodology.

    “reporting guidelines are not recommendations for designing or conducting studies, although they may contribute to improving methodology.14”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [14] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    The draft checklist was published as a preprint in July 2019 and debated on the preprint platform, Twitter, and at the 4th Mendelian Randomization Conference.

    “The draft checklist was published as a preprint in July 2019 18 and debated on the preprint platform, Twitter, and at the 4th Mendelian Randomization Conference.19”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    Drs Skrivankova and Egger had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

    “Drs Skrivankova and Egger had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    Development of STROBE-MR was informed by the EQUATOR Network's methodological framework for guideline development.

    “Development of STROBE-MR was informed by the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network's methodological framework for guideline development.14”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [14] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning

    The STROBE-MR checklist is based on input from a large number of individuals with diverse backgrounds and perspectives, gathered through an extensive iterative consultation process with consecutive drafts.

    “with consecutive drafts subjected to an extensive iterative process of consultation.Thus, the checklist presented herein is based on input from a large number of individuals with diverse backgrounds and perspectives.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    The funders/sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

    “The funders/sponsors had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation review, or approval of the manuscript; and decision to submit the manuscript for publication.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    The statement does not describe all methods that can be used to assess all of the assumptions required within a mendelian randomization study.

    “the statement attempts to provide comprehensive reporting guidelines and describe their generation, but does not describe all methods that can be used to assess all of the assumptions that are required within a mendelian randomization study.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductnone given

    The relevant empirical evidence on the reporting of Mendelian randomization studies was reviewed, and the first draft of the STROBE-MR checklist was piloted on recently published Mendelian randomization studies, with consecutive drafts subjected to an extensive iterative process of consultation.

    “The relevant empirical evidence on the reporting of mendelian randomization studies was reviewed, and the first draft of the STROBE-MR checklist was piloted on recently published mendelian randomization studies, with consecutive drafts subjected to an extensive iterative process of consultation.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The major assumptions of mendelian randomization and commonly used methods to assess their validity have been described in the statement.

    “Nevertheless, the major assumptions and commonly used methods to assess their validity have been described.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Study design and conductreasoning

    The comprehensive E&E document also benefited greatly from the consultation process used to develop the checklist.

    “The comprehensive E&E document, 15 which is intended for use alongside the checklist, also benefited greatly from this consultation process.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [15] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    A systematic review has not been undertaken to better understand reporting deficiencies in mendelian randomization studies.

    “Third, a systematic review has not been undertaken to better understand reporting deficiencies in mendelian randomization studies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    Dr Golub, JAMA Deputy Editor, was not involved in the evaluation or review of this manuscript, or in the decision regarding publication.

    “Dr Golub, JAMA Deputy Editor, was not involved in the evaluation or review of this manuscript, or in the decision regarding publication.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    Reporting guidelines, such as the STROBE guideline, can improve reporting quality.

    “Reporting guidelines, such as the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline, 13 can improve reporting quality.14”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [14] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Feedback from the community has been sought and incorporated in the development of the STROBE-MR statement.

    “as with any consensus document, feedback from the community has been sought and incorporated, and future iterations of this document will be updated to incorporate further feedback from individuals interested in undertaking and interpreting mendelian randomization studies.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable), S4 (based). May combine two claims.

    Interpretationnone given

    Improved reporting of mendelian randomization studies could facilitate their evaluation by editors, peer reviewers, researchers, clinicians, and other readers, and enhance the interpretation of their results.

    “Improved reporting of these studies could facilitate their evaluation by editors, peer reviewers, researchers, clinicians, and other readers, and enhance the interpretation of their results.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Reporting of mendelian randomization studies is currently deficient and stands to be improved.

  • Classified as probably not a substantial claim.

    Study design and conductcitation

    The STROBE checklist was used as the point of departure, thoroughly modifying and adapting it to Mendelian randomization studies through an open process in accordance with the guidance for developers of reporting guidelines.

    “The STROBE checklist was used as the point of departure, thoroughly modifying and adapting it to mendelian randomization studies through an open process in accordance with the guidance for developers of reporting guidelines.14”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [14] source

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    The STROBE-MR checklist is not an instrument to evaluate mendelian randomization research quality and should not be used for that purpose.

    “the checklist is not an instrument to evaluate mendelian randomization research quality, and it should not be used for this purpose.29”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [29]

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    A formal Delphi process was not performed.

    “A formal Delphi process was not performed.”
    Quote in the paperNot a substantial claim
36 of 36

  • The paper relies on this without support.

    Mendelian randomization studies use genetic variants that are reliably associated with exposures of interest but do not vary with correlated lifestyle or socioeconomic factors that may confound conventional observational associations.

    “Mendelian randomization studies use genetic variants, typically single-nucleotide polymorphisms (SNPs), that are reliably associated with exposures of interest but do not vary with the correlated lifestyle or socioeconomic factors that may confound conventional observational associations.”

  • The paper relies on this without support.

    The number of published Mendelian randomization studies increased from 1 report in 2003 to more than 800 articles in 2020.

    “In recent decades, the number of published mendelian randomization studies has increased rapidly, from 1 report in 2003 to more than 800 articles in 2020.”

  • The paper relies on this without support.

    The 20 randomly selected 2018 Mendelian randomization articles are representative enough to confirm reporting deficiencies in Mendelian randomization studies.

    “Of 404 potentially eligible articles (as of April 1, 2019), 20 were randomly selected and scanned to determine whether they contained original research.”

  • The paper relies on this without support.

    The expert consensus process used, without a formal Delphi process, yields a valid reporting guideline.

    “A formal Delphi process was not performed.”

  • The paper relies on this without support.

    Reporting of mendelian randomization studies is currently deficient and stands to be improved.

    “Third, a systematic review has not been undertaken to better understand reporting deficiencies in mendelian randomization studies.”
5 of 5

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Cites

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1 of the 31 references couldn’t be matched to a known paper.

Research works printed but not linked: 1

  1. MRC Integrative Epidemiology Unit, University of Bristol. 4th Mendelian Randomization Conference 2019. Accessed July 10, 2019. https://www.bristol.ac.uk/integrative-epidemiology/seminars/2019/mr-conference-2019.html

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Authors
Skrivankova, V. W., Richmond, R. C., Woolf, B. A. R., Yarmolinsky, J., Davies, N. M., Swanson, S. A., VanderWeele, T. J., Higgins, J. P. T., Timpson, N. J., Dimou, N., Langenberg, C., Golub, R. M., Loder, E. W., Gallo, V., Tybjaerg-Hansen, A., Davey Smith, G., Egger, M., & Richards, J. B.
Affiliations
  • University of Bern (CH)
  • University of Bristol (GB)
  • Norwegian University of Science and Technology (NO)
  • Erasmus MC (NL)
  • Harvard University (US)
  • Centre international de recherche sur le cancer (FR)
  • University of Cambridge (GB)
  • Northwestern University (US)
  • Brigham and Women's Hospital (US)
  • University of London (GB)
  • Section for Molecular Genetics, Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
  • Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
Corresponding author
Richards, J. Brent
ORCID
Venue
JAMA
Publisher
American Medical Association (AMA)
Published
2021-10-26
Volume
326
Issue
16
Pages
1614
ISSN
  • 0002-9955 (ISSN-L)
  • 0098-7484
DOI
10.1001/jama.2021.18236
OpenAlex
W3210570897
Semantic Scholar
e546bc8b0563867fb604350635927b738d676dff
Cited by
3,994
References
31
Citations by year
2026: 711 · 2025: 1296 · 2024: 1358 · 2023: 470 · 2022: 153 · 2021: 4
FWCI
297.95
Type
journal article
Language
en
Open access
Licence
cc-by
Locations
  • JAMA (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Research at the University of Copenhagen (University of Copenhagen) (publishedVersion, other-oa)
  • EUR Research Repository (Erasmus University Rotterdam) (publishedVersion, cc-by)
  • EUR Research Repository (Erasmus University Rotterdam) (submittedVersion, cc-by)
  • BORIS (University Library Bern) (submittedVersion)
  • University of Groningen research database (University of Groningen / Centre for Information Technology) (submittedVersion, other-oa)
  • Explore Bristol Research (submittedVersion)
Funders
  • World Health Organization
  • Wellcome Trust (202802/Z/16/Z)
  • National Institute for Health and Care Research (NF-SI-0617-10145)
  • Medical Research Council (MC_UU_00011/5, MC_UU_00011/1)
  • Economic and Social Research Council (2094259)
Topics
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetic Associations and Epidemiology
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Keywords
Mendelian randomization, reporting guidelines, reporting checklist, observational studies, causal inference, instrumental variables, genetic variants, confounding, reverse causality, data sharing, reproducibility, EQUATOR Network
MeSH terms
Epidemiology, Humans, Pilot Projects, Bias, Guidelines as Topic, Information Dissemination, Genome-Wide Association Study, Mendelian Randomization Analysis, Checklist, Social Media, Observational Studies as Topic

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