Reviewe r’s report  
 
Title: Gender norms and modern contraceptive use in urban Nig eria: a multilevel longitudinal 
study  
 
Version: 0 Date: 24 Jun 2016  
 
Reviewer: Tia Palermo  
 
Reviewer's report:  
 
This study uses data from a longitudinal study in six cities in Nigeria to examine the relationship 
between individual - and community -level attitudes on domestic violence, decision -making, and 
family planning on w omen's use of modern contraceptives. The authors use multinomial models 
to account for the non -ordinal, multi -categorical nature of changes in contraceptive use (i.e., 
continued user, discontinuer, adapter, non -user) and account for the clustered nature of  the 
sample through the use of multi -level models. The paper's contribution to the literature, while not 
unique in any one aspect, is through its combination of the geographical area of focus, its use of 
longitudinal data, and use of community -level attitu des. The measures of empowerment utilized 
are the standard measures ranging from opinions about domestic violence and decision -making 
collected in routine DHS surveys to family planning efficacy questions common in family 
planning research. However, the au thors note that there is a geographic gap in the literature, 
where most of the existing evidence on empowerment on fertility/contraceptive use comes from 
South Asia. Finally, they examine the influence of "community norms" as measured by 
aggregate indicato rs of the individual -level responses on these topics.  My suggestions on how to 
improve the paper are as follows, grouped by major and minor issues.  
 
 
 
Major issues  
 
1. Some critical descriptive statistics and basic tests are missing from the summary ta bles. 
First, attrition analysis is needed to determine whether baseline characteristics differ 
between women who were lost at follow -up (>30% of the sample) versus those 
interviewed at endline and a discussion of how this might affect the findings.  
 
 
2. Second, summary statistics are needed for the individual - and community -level variables 
created for use in the analysis. That is to say, what percentage of women are in the 
categories low to low, low to high, high to low, and high to high?  
 
 
3. More in formation on the intervention would be helpful, even though this is not an 
evaluation of the impacts of the intervention, but rather to understand why we might 
expect gender norms (particularly at the community level) to change in a short time 
period (four  years).  
4. P18 - authors say they estimated relative risks, but the tables say they reported 
exponentiated coefficients from logistic models, which should give you odds ratios, not 
risk ratios.  
 
 
5. Before examining the relationship between change s between categories of the predictors 
and the outcome, it would be interesting to see the relationship between absolute values 
of the predictors, for example through a conditional logit/fixed effects logit model. In this 
way you can also use the continuou s independent variable.  
 
 
6. I'm not convinced by the value of how the community -level information is utilized. It 
would be helpful as stated above to see what percentage of women live in communities 
that "shifted" attitudes, as I would expect it to be small. Also, community norms from a 
theoretical perspective are unlikely to have changed in such a small time period, even if 
you can see change based on arbitrary cut -offs in the data. To address this, it would be 
better to either utilize the continuous s core average at the community -level or baseline 
values of "norms".  
 
 
 
Minor issue  
 
1. P2, first para - double check the statistic cited from the Ahmed et al. study; I believe the 
percentage for Nigeria is 19% which translates to one in five, not one in f our as currently 
cited.  
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary cont rols?  
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 your comments to the authors.  
 
Yes 
 
 
Are you able to assess any statistic s in the manus cript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please speci fy 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 salar y from an 
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3. Do you hold or are you currently applying for any patents  relating to the content of the 
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4. Have you received reimbursements, fees, funding, or salary from an organi zation 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?  
 
 
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below. If your reply is yes to any, please give details below.  
 
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