Title: Trends in maternal mortality in Latin America and the Caribbean: A joinpoint analysis
Version: 0 Date: 13 Apr 2025
Reviewer:  Kevin Martinez-Folgar
Reviewer's report:
Thank you for the opportunity to review this manuscript examining maternal mortality trends
across Latin America and the Caribbean from 1997 to 2020.
Overall, I found the manuscript to be clearly written and policy-relevant. However, there are
several areas where the analysis and interpretation could be further strengthened.
First, while the use of standardized international datasets is a strength, it is important to
acknowledge the limitations inherent in these sources, especially when working with maternal
mortality data in LMIC countries. Issues such as undercounting of maternal deaths and
misclassification due to incomplete or inaccurate use of ICD10 codes can bias trend estimates.
I see that the authors mention it as a limitation but would recommend that the authors include a
discussion on how these data limitations might have affected their results and how to assess the
potential direction of those effects. If feasible, a sensitivity analysis to explore the robustness of
their findings in light of potential misclassification or under-registration could add value.
Second, because the number of maternal deaths in several countries is relatively low, I suggest
that the authors present absolute measures such as rate differences in addition to the relative
measures (i.e., APC and AAPC). This could provide a more complete picture of the changes in
maternal mortality over time, especially for policymakers seeking to interpret the magnitude of
change in concrete terms and not just in relative numbers.
Third, I encourage the authors to provide greater detail on the Joinpoint regression analysis.
Specifically, it would be useful to know how many joinpoints were allowed for each country,
and whether this was determined in a data-driven way or fixed a priori. In countries with small
sample sizes or fewer deaths per year, Joinpoint can overfit the data, so transparency around
these decisions is important.
To assess the robustness of the trend estimates, it may also be helpful to consider a sensitivity
analysis using a simpler modeling approach, such as Poisson regression with time as a
continuous variable. This could serve as a useful check on whether the identified trends are
consistent across modeling frameworks.
Another important point relates to the quality and consistency of the denominator used for the
maternal mortality ratio. Live birth registration data can vary considerably in completeness
and accuracy across countries in the region. The authors could strengthen the manuscript by
addressing how this may influence their MMR estimates, and by referencing any known issues
with birth data completeness in the region.
The manuscript would also benefit from enhanced data visualization. Line plots showing
ASMR and MMR trends by country, particularly highlighting those with statistically significant
changes, would help readers visualize the differences across settings more effectively.
Finally, if the data allow, it would be valuable to examine whether trends differed by key
subgroups—such as maternal age or geographic region (e.g., rural vs. urban). If such analyses
are not possible, this could be acknowledged as a limitation.
In sum, this manuscript addresses an important issue and offers useful insights for the region.
With some additional clarification around the data sources, and analytic methods, the paper
could make a strong contribution to the literature on maternal health inequalities.