Title: The effect of waiting time on ovarian cancer survival in oncology centres, Addis Ababa,
Ethiopia: a retrospective cohort study
Version: 0 Date: 30 Dec 2024
Reviewer:  Vipin Thampi
Reviewer's report:
Major Concerns
Clarity of Research Question:
The manuscript lacks a clearly defined research question or hypothesis in the introduction. A
more explicit statement would strengthen the focus.
Methodological Gaps:
Sampling Bias: The study uses a census sampling technique but excludes incomplete medical
records, introducing potential bias that is not fully addressed in the limitations.
Validation of Data Tools: While the authors mention pre-testing the data abstraction format,
they do not provide sufficient details about how validation was carried out or its reliability.
Confounders: Although adjustments were made, the manuscript does not elaborate on the
rationale for selecting specific covariates in the multivariable analysis.
Model Assumptions: The Schoenfeld residuals test is briefly mentioned, but further details on
how assumptions were checked and met are missing.
Statistical Analysis:
There is no justification for choosing the 10-week threshold for waiting time. Additional
sensitivity analysis or references supporting this cut-off would enhance credibility.
The Kaplan-Meier analysis and Cox regression results are presented but lack visual
representation (e.g., survival curves for subgroups).
Interpretation of Results:
The discussion does not critically compare findings to global studies beyond a surface level.
Contradictory findings are acknowledged but not explored deeply.
The manuscript does not discuss potential socio-cultural or systemic factors specific to Ethiopia
that might explain the observed delays in treatment initiation.
Minor Concerns
Language and Formatting:
There are grammatical errors (e.g., "wating" instead of "waiting" in the abstract) and awkward
phrasing throughout.
References to statistical software (e.g., STATA Version 17) could be standardized for
consistency.
Inadequate Background Context:
The introduction does not adequately discuss Ethiopia-specific barriers to ovarian cancer care,
such as healthcare infrastructure or patient demographics.
Table Representation:
Some tables (e.g., Table 1 and Table 2) lack clarity in column headings and would benefit from
concise titles and notes explaining abbreviations.
Ethical Considerations:
Although ethical approval is mentioned, the absence of individual informed consent due to
reliance on retrospective data warrants a more detailed ethical justification.
Conclusion:
The conclusion lacks actionable policy recommendations or future research directions, which
could enhance its relevance for practitioners.
Recommendations
Substantive Revision:
Address the methodological gaps, especially around sampling bias and justification for the
statistical thresholds used.
Include additional sensitivity analyses or subgroup survival curves to provide more robust
evidence.
Contextualization:
Broaden the discussion to include socio-cultural and healthcare system factors unique to the
study setting.
Language Editing:
Engage a professional editor or service to enhance readability and correct grammatical errors.
Data Privacy , Confidentiality and Informed consent  :
Expand the ethical considerations section to address potential concerns about data privacy and
the lack of informed consent.
Actionable Insights:
Strengthen the conclusion with specific recommendations for policy and clinical practice.
Overall Recommendation: Major Revision
This manuscript addresses a critical issue in cancer care but requires significant improvements
in methodological rigor, contextual relevance, and presentation quality to meet publication
standards.