Review for 10.1186/s12876-025-03805-2 (2025)

Title: MAFLD Mediates the Association Between CHR and Gallstones in the U.S. Adults:
Evidence from NHANES 2021-2023
Version: 1 Date: 06 Feb 2025
Reviewer:  Amira A A Othman
Reviewer's report:
First of all
I want to congratulate the authors on their work. In this study, Feng et al. aimed to explore
the association between the high-sensitivity C-reactive protein-to-high-density lipoprotein
cholesterol ratio (CHR) and gallstones, with a focus on the potential mediating role of
nonalcoholic fatty liver disease (NAFLD). Given the rising prevalence of gallstones and
NAFLD, understanding the underlying inflammatory and lipid metabolism pathways could
provide valuable insights into disease prevention and management. By utilizing data from the
National Health and Nutrition Examination Survey (NHANES), this study employs advanced
statistical models to elucidate the interplay between inflammation, lipid abnormalities, and
gallstone formation.
Non-alcoholic fatty liver disease (NAFLD) is recognized as the most prevalent chronic liver
disease, impacting about 30% of global individuals, with the potential to progress to advanced
hepatic fibrosis and end-stage liver diseases eventually [*]. In June 2023, a multi-society
committee of international experts was gathered, and new terminology was adopted to reduce
stigma and increase disease awareness [**]. A new terminology, Steatotic liver disease (SLD),
replaces “fatty liver disease” as the umbrella term. Under subgroups of SLD, NAFLD has been
renamed as metabolic dysfunction-associated Steatotic liver disease (MASLD) [**]. NAFLD/
MASLD is closely related to metabolic syndrome (MetS) and its associated components of
hypertension, type 2 diabetes mellitus, dyslipidemia, and obesity[***].
(*:doi: 10.1097/HEP.0000000000000004, **: doi: 10.1016/j.jhep.2023.06.003, ***  doi:
10.1111/apt.17308).
The authors handled the reviewer comments satisfactorily, nevertheless, there is an observation
for which sufficient justification must be obtained.
In general:
1. The writing quality needs improvement, and it would be beneficial to consult an English
language expert to address spelling and grammatical issues throughout the text.
2. Abbreviations must be fully written at their first appearance.
In Title:
1. The title should indicate the age and locality of the study population at which the National
Health and Nutrition Examination Survey (NHANES) was performed. , I suggest “ MAFLD
Mediates the Association Between CHR and Gallstones in U.S. Adults: Evidence from
NHANES 2021-2023”.
In Abstract section
2. The background subsection in the abstract :
-  Should be the shortest part of the abstract. It should briefly outline the following information:
What is already known about the subject, related to the paper in question. What is not known
about the subject and hence what the study intended to examine (or what the paper seeks to
present)? Please reconstruct it properly.
3.  The type of study: a population-based study.
4. In the method subsection in the abstract :
- Nothing was mentioned about the participant's age, sex, ethnicity, etc.
- It would help if you described the aim of your statistical analysis.
- Clarify study design and analysis techniques: “This cross-sectional study analyzed NHANES
data (2021–2023) using weighted logistic regression, restricted cubic splines (RCS), and
mediation analysis.”
5. In the results subsection in the abstract :
-   Improve numerical clarity and conciseness: “Among 4,078 participants, 432 (10.60%) had
gallstones. After adjusting for confounders, each unit increase in CHR was associated with a
165% increased risk of gallstones (OR: 2.65, 95% CI: 1.43–4.93, P = 0.006). Mediation analysis
indicated MAFLD explained 27.1% of this association."
6. In the conclusion subsection in the abstract :
- Emphasize the clinical significance of your study: "CHR is positively associated with
gallstones, with NAFLD partially mediating this relationship. Managing CHR levels and
preventing NAFLD may reduce gallstone incidence."
In the Introduction section:
7. Try to provide a summarized description of The National Health and Nutrition Examination
Survey (NHANES) in the background section. You may use the following: “NHANES
(www.cdc.gov/nchs/nhanes) is designed to assess the health and nutritional status of adults
and children in the United States. The survey is distinctive in that it incorporates both
physical examinations and interviews. Several cross-sectional, nationally representative health
examination surveys are part of the NHANES program. Questions about demographics,
health insurance status, dietary habits, acute and chronic medical issues, mental health, and
prescription drug use are all included in the health interview. Exam components can change
between survey cycles but typically include blood pressure, dental exams, vision, hearing,
dermatology, fitness, balance and strength testing, respiratory testing, taste and smell, and
body measurements (weight, height, skin folds, body composition scans). Hematology, organ
and endocrine function (e.g., thyroid, kidney), environmental exposure, dietary biomarkers,
metabolic and cardiovascular health, and infectious disease are a few examples of laboratory
components.”.
8. MAFLD must replace NAFLD:
“In contrast to NAFLD, MAFLD does not necessitate ruling out other liver disease causes, such
as viral hepatitis or heavy alcohol use*. The new name chosen to replace NAFLD reflected the
disease etiology better and conveyed a more practical approach in daily clinical practice than
NAFLD, considering its close association with metabolic syndrome**. Please discuss the new
nomenclature in more detail.
(*: Doi: 10.1016/j.jhep.2020.03.039, **: doi: 10.1097/HEP.0000000000000520)
9. Highlight why CHR is an important biomarker and explain inflammation/lipid metabolism
to gallstone risk.
10. State your study hypothesis (link between CHR, NAFLD, and gallstones)
In the Methods section:
11. Please move the sentences defining the NHANES to the introduction section rather than the
methodology section.
12. The study utilized the 2021-2023 NHANES survey cycle, why did you choose the study
survey cycle? The survey includes study cycles from 2001 to 2023.
13. Please provide the participants' sociodemographic data.
14. How the sample size was calculated.
15. Mention ethical approval earlier in the methodology to emphasize compliance.
16. Provide more details on the exclusion criteria to ensure reproducibility (e.g., specific
thresholds for "missing data").
17. Statistical analysis:
-   The Mann–Whitney U test is a nonparametric test and involves the summation of ranks. The
Mann–Whitney U test is applied to independent samples. T-test is used to compare the mean of a
continuous variable between a maximum of 2 groups. The Kruskal–Wallis test is a statistical test
used to compare two or more groups for a continuous or discrete variable. The Wilcoxon rank-
sum test is used to compare two independent samples, while the Wilcoxon signed-rank test is
used to compare two related samples, matched samples, or to conduct a paired difference test of
repeated measurements on a single sample to assess whether their population mean ranks differ.
Analysis of variance (ANOVA) is a statistical test used to assess the difference between the
means of more than two groups. How did you choose the proper test during your result analysis?
In the Results section:
18. In all tables, please explain the abbreviations under tables.
19. You can title the statistical test column as “Test of significance” and use U= for the Mann–
Whitney U test, T= for the T-test, and #2 = for the Chi-square test, etc., Although the Chi-square
test was used to compare observed and expected results, nothing was mentioned in the statistical
analysis section.
20. Ensure that table captions succinctly describe the content for standalone clarity.
In the Discussion section:
21. The discussion section is one of the final parts of a research paper, in which an author
describes, analyzes, and interprets their findings. They explain the significance of those results
and tie everything back to the research question(s). In this manuscript, there is confusion
between what should be written in the introduction and discussion sections. Please reconstruct
the discussion section.
22. Discuss how the random forest model's predictive performance translates into clinical
practice.
23. Discuss the novelty of your study regarding previously published papers (if present).
24. Emphasize self-reported gallstone diagnosis as a key limitation.
25. Suggest longitudinal studies to confirm causality.