Reviewer ’s report  
 
Title: Use of contraceptives, high risk births and under -5 mortality in Sub Saharan Africa: 
Evidence from Kenyan (2014) and Zimbabwean (2011) Demographic Health Surveys  
 
Version: 1 Date: 24 Feb 2018  
 
Reviewer: Ties Boerma  
 
Reviewer's report:  
 
Review - BMC Contraception  
This paper addresses a priority topic for maternal and child healt h in Africa and that is the 
association with fertility. It presents a solid analysis for two countries using DHS surveys and 
applies a comprehensive set of methods of analyses.  
My main comments are the lack of new insights that this analysis appears to b e generating. It 
would be useful if the authors could further emphasize in the paper why this is an important 
contribution to the field:  
Numerous studies have addressed the topic of contraceptive use, high risk births and mortality,  
particularly for sub -Saharan Africa.  
 There is an extensive body of research on factors influencing contraceptive use. Most 
prominently, contraceptive use is closely associated with higher levels of socioeconomic 
status and place of residence (urban - rural).  
 
 Contraceptive  use is also associated with lower fertility, which generally is associated with 
longer birth intervals, fewer births to very young or very old women and fewer high parity 
births - in other words, fewer high risk births as defined in the paper.  
 
 Contracep tive use is also associated with lower under -5 mortality, either because of its 
association with socioeconomic status but also independently through its effect on lowering 
high risk births.  
The authors state that "However, there is scarcity of data explor ing the relationship between 
contraceptive use, high risk births, and child mortality as determined by their geospatial 
distribution and contextual community factors." I am not sure I agree with that statement but was 
curious to see whether their geospatia l analysis would provide new insights. The results are 
disappointing. The geospatial and multi -level analyses seem to give little new insight into the 
topic. For instance, the first sentences of the conclusion "The relative low prevalence of 
contraceptive use in both countries suggest that more effort should still be focused on increasing 
contraceptive coverage and reducing the unmet need for modern contraceptive use. The 
improvement in contraceptive usage would yield benefits by reducing the number of high -risk 
births and under -five mortality."  The paper seems to partly contradict this finding in the results 
and discussion, as their analysis showed that in Zimbabwe, modern contraceptive use was 
protective against both high risk births and under -five mortal ity whilst in Kenya it was only 
significantly protective against under -five mortality.  
Much of the paper's ideas and work seems to be based on a paper published in 2015 by Maïga A 
et al. with a similar subject and title but focusing on Burkina Faso (Trend s and patterns of 
modern contraceptive use and relationships with high -risk births and child mortality in Burkina 
Faso). The authors refer to this paper in the discussion but do add further analytical approaches 
and use different country datasets, but over all seem to confirm the conclusions.  
Community factors analyses: this is a further contribution of the paper, but in terms of new 
insights it would be good to describe better what these analyses contribute. For high risk births, 
the community factors do not appear to matter at all after taking into account the individual level 
variables. For under -5 mortality, the community variables completely switch sign after the 
control for individual level variables with rural mortality lower than urban mortality in both 
countries. The authors try to explain this finding in the discussion and attribute it to poor living 
conditions and poor quality of care in the urban areas or recent migration, but I find their 
treatment of this quite unsatisfactory. This would need t o be addressed much more thoroughly.  
 
Minor point:  
One limitation that is not mentioned: Contraceptive prevalence/use is current, under -5 mortality 
and high risk births refer to the past 5 years.  
Are the methods appropriate and well described?  
If not, please specify what is required in your co mments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in you r comments to the authors.  
 
No 
 
  
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further  
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publi cation of this  
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you curr ently applying for any patents relating to the content of the  
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any  other financial competing interests?  
6.  
Do you have any non -financial competing interests in relation to this paper?  
 
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below.  If your reply is yes to any, please give details below.  
 
I declare that I have no competing interests  
 
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