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Mendelian Randomization Studies: A Metric for Quality Evaluation
Fiorella Rosas-Chavez1, Tony R Merriman1,2
1Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
Gout, Urate, and Crystal Deposition Disease
|July 23, 2026
Summary
This study assessed the quality of Mendelian randomization (MR) studies on hyperuricemia and gout, finding significant variability. A new scoring system was developed to help evaluate these genetic epidemiological studies.
Area of Science:
- Genetic Epidemiology
- Biostatistics
- Public Health
Background:
- Mendelian randomization (MR) is a key method for inferring causal links between exposures and outcomes.
- Its use in hyperuricemia and gout research has surged due to accessible genome-wide association study data and efficient two-sample MR techniques.
- Concerns regarding study quality necessitate systematic evaluation.
Purpose of the Study:
- To evaluate the methodological quality of two-sample MR studies investigating hyperuricemia and gout.
- To develop and propose a scoring system for assessing the validity and quality of these MR studies.
Main Methods:
- A systematic review of 86 two-sample MR studies published from 2016 to 2024 was performed.
- A scoring system was developed, covering study design, statistical methods, result interpretation, and STROBE-MR adherence, with a potential range of -9 to 21.
- Regression models were used to analyze quality trends over time.
Main Results:
- Study quality scores varied widely, from 0 to 19 (mean 9.1, median 11).
- High-quality studies met MR assumptions, used independent data, and included replication analyses.
- Lower-quality studies often lacked p-value correction, confounder testing, dataset overlap checks, or power reporting. Overall quality has not improved despite increased publications.
Conclusions:
- Significant variability exists in the quality of two-sample MR studies concerning hyperuricemia and gout.
- The proposed scoring system provides a practical tool for researchers and clinicians to assess MR study validity.
- This framework aims to enhance the identification of robust findings and promote higher methodological standards in the field.
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