Review for 10.1186/s12876-025-03822-1 (2025)

Title: The prevalence of Barrett 's esophagus in Iranian patients with gastrointestinal symptoms:
a systematic review and meta-analysis
Version: 2 Date: 30 Dec 2024
Reviewer's report:
Background:
1- Problem definition:
- The problem definition is partially clear but could be made more explicit. The background
highlights the clinical significance of Barrett's Esophagus (BE) and the challenges related to
its diagnosis and prevalence estimation. However, it does not succinctly articulate the specific
problem this study aims to address, namely, the lack of comprehensive prevalence data for BE in
Iran. Additionally, while the global context is relevant, the transition to the Iranian context could
be smoother and more focused. It would be beneficial to emphasize why this data is particularly
critical for Iran.
2- Type of study design used:
- The background does not specify the types of studies (e.g., observational, cross-sectional,
cohort) that will be included in the systematic review and meta-analysis.
Method:
1- Method of Addressing Articles Published in Languages Other than English:
- It seems that this part of the methods section ("No publication date restrictions were applied
during the search process") is repetitive, as it was already mentioned earlier in the sentence:
"...databases including SID and Magiran, using standard keywords from inception to the end
of 2023."
- In the search strategy, it is mentioned that a letter was sent to all research centers to ensure
all related studies were included. It would be clearer to specify that the letter was sent to all
relevant research centers.
2- Use of Hand Searching:
- The authors contacted research centers but did not mention hand-searching reference lists of
included articles.
3- Method of Addressing Articles Published in Languages Other Than English:
-  It mentioned no language restrictions but do not specify how non-English articles were
handled.
4- Study selection:
- The inclusion criteria were not mentioned clearly. Additionally, regarding excluded study
designs, it would be better to explicitly add "interventional studies" to the list.
5- Data extraction and quality assessment
- In the sections "(...the title and abstract of records (n=479) were screened by two independent
investigators)," "(...two investigators extracted data independently and cross-checked it)," and
"(Two researchers investigated study quality independently, using the Newcastle-Ottawa Scale
(NOS) for cross-sectional studies)," it is recommended to include the abbreviations or initials
of the reviewers for clarity and accountability.
- It is recommended to provide more information about the Newcastle-Ottawa Scale (NOS),
including details on the scoring system, the range of possible scores, and the criteria used to
categorize studies as poor or high quality.
- It is recommended that in the PRISMA diagram, the articles found through other methods (e.g.,
SID and similar databases) be merged with those found in other databases.
6- Rationale for Selection and Coding of Data:
- The rationale for extracting specific data (e.g., region, prevalence, diagnostic criteria) is implied
but not explicitly stated. Explain why specific variables were chosen for extraction (e.g., to
assess variability in prevalence across regions and diagnostic criteria).
Result:
- Adding a column to summarize the Newcastle-Ottawa Scale (NOS) scores for each study.
- Results of Sensitivity Testing: Clearly explain the rationale for excluding the outlier and its
impact on the overall estimates.
Discussion:
- Indication of Statistical Uncertainty of Findings:
- Consider discussing the limitations of high heterogeneity in the Discussion section.
Conclusion:
Consideration of Alternative Explanations for Observed Results:
- The conclusion does not address alternative explanations for the observed results. While the
importance of timely diagnosis and the need for more studies are emphasized, potential biases,
heterogeneity, or alternative interpretations of the prevalence estimates are not considered.
Overall comment:
It is generally recommended to revise the manuscript to the academic English writing.