Reporting and guidelines for mendelian randomization analysis: A systematic review of oncological studies
Abstract
Background Mendelian randomization (MR) analyses have been increasingly used to seek evidence of causal associations. This systematic review aims at characterizing and evaluating the reporting of MR analyses in oncological studies.Methods The PubMed database was searched to identify MR cancer studies until December 31, 2017. Two of the authors independently selected and evaluated reporting quality of the studies. Reporting quality in MR studies before 2016 and in 2016/17 was compared.Results Cancer studies with MR analyses in 2016 and 2017 accounted for 55.8% of the total number of studies identified. In the 77 eligible articles, 39 (50.6%) did not report subjects' characteristics, 53 (68.8%) did not conduct power estimation, 40 (51.9%) did not state all of the first three MR assumptions (i.e., genetic instrument is associated with exposure, is not associated with confounders, and acts on outcome only through exposure), and 31 (40.3%) did not exclude SNPs that diverged from Hardy-Weinberg equilibrium. More studies estimated power in 2016/2017 than before 2016 (p = 0.028).Conclusions Some MR cancer studies did not sufficiently report essential information, posing obstacles for critical appraisal. This study proposes for MR analysis a guideline/checklist for future publications in cancer and other biomedical research.
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Published evidence from Mendelian randomisation studies is often hampered by inadequate reporting.
“but the published evidence is often hampered by inadequate reporting”
From Strengthening the Reporting of Observational Studies in Epidemiology using Mendelian Randomisation (STROBE-MR): explanation and elaboration. (2021) · cites this paper as [23]
Many reports of Mendelian randomisation studies report insufficient details on the data sources.
“and report insufficient details on the data sources”
From Strengthening the Reporting of Observational Studies in Epidemiology using Mendelian Randomisation (STROBE-MR): explanation and elaboration. (2021) · cites this paper as [23]
The quality of reporting of Mendelian randomisation studies has been inconsistent.
“As a result, the quality of reporting of these studies has been inconsistent.”
From Strengthening the Reporting of Observational Studies in Epidemiology using Mendelian Randomisation (STROBE-MR): explanation and elaboration. (2021) · cites this paper as [23]
Many reports of Mendelian randomisation studies do not clearly state or examine the various assumptions of Mendelian randomisation methods.
“Empirical evidence22 23 24 indicates that many reports of MR studies do not clearly state or examine the various assumptions of MR methods”
From Strengthening the Reporting of Observational Studies in Epidemiology using Mendelian Randomisation (STROBE-MR): explanation and elaboration. (2021) · cites this paper as [23]
Little consensus exists around the reporting of Mendelian randomisation studies.
“Despite the growth in MR applications and methods and the increasing relevance of MR findings, little consensus exists around the reporting of MR studies.”
From Strengthening the Reporting of Observational Studies in Epidemiology using Mendelian Randomisation (STROBE-MR): explanation and elaboration. (2021) · cites this paper as [23]
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- Authors
- Lor, G. C. Y., Risch, H. A., Fung, W. T., Au Yeung, S. L., Wong, I. O. L., Zheng, W., & Pang, H.
- Affiliations
- University of Hong Kong (HK)
- Yale University (US)
- Vanderbilt University Medical Center (US)
- Corresponding author
- Pang, Herbert
- Venue
- Cancer Epidemiology
- Publisher
- Elsevier BV
- Published
- 2019-10
- Volume
- 62
- Pages
- 101577
- ISSN
- 1877-7821 (ISSN-L)
- OpenAlex
- W2966470836
- Cited by
- 27
- References
- 39
- Citations by year
- 2026: 1 · 2025: 6 · 2024: 6 · 2023: 1 · 2022: 10 · 2021: 2 · 2020: 1
- FWCI
- 0.66
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Cancer Epidemiology (publishedVersion)
- PubMed (publishedVersion)
- Funders
- University of Hong Kong
- 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 quality, cancer research, causal inference, power estimation, Hardy-Weinberg equilibrium, genetic instruments, reporting guidelines, critical appraisal
- MeSH terms
- Humans, Neoplasms, Guidelines as Topic, Mendelian Randomization Analysis
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