Reviewer ’s report  
 
Title: Intimate partner violence against women in Nigeria: a multilevel study investigating the 
effect of women's status and community norms.  
 
Version: 0 Date: 28 Mar 2018  
 
Reviewer: Daniel Adeyinka  
 
Reviewer's report:  
 
Intimate par tner violence against women in Nigeria: a multilevel study investigating the effect of 
women's status and community norms.  
 
Reviewer: Daniel Adeyinka  
I was pleased to review this manuscript ("intimate partner violence against women in Nigeria: a 
multileve l study investigating the effect of women's status and community norms.") for BMC 
Women's Health.  
 
Importance of the study  
Although IPV against women is widespread in Nigeria and many other developing countries, the 
existing domestic violation law is not sufficient to curb this menace. Violation of the human 
rights of women is detrimental to their health and those of children. Reports indicate that IPV is a 
product of social context but the validity of these reports is unclear with very little knowledge 
about the role of community influences on women's experience of IPV. This paper gives us some 
context due to the large validated population -based dataset. This analysis is required to fill the 
research gap in the country and other similar settings, and infor m strategies that will address this 
issue. Also, it is important to disseminate data on IPV in various international settings. For that 
reason and because I believe the result on the importance of addressing the community norms 
and women's status might add  productively to extant knowledge on this topic, I think the paper 
has potential to make a worthwhile contribution to the literature. However, the manuscript 
requires significant work by the authors and major revisions to be publishable.  
I have listed my  primary concerns under the appropriate headings. I sincerely hope these are 
helpful to the authors in improving the manuscript.  
 
 
Comments to the authors  
Title  
It is appropriate.  
 
Abstract  
Rather than specifying the sample frame of 21,004 ever -partnered women, it would be helpful to 
state the final sample size of 20,802 women used for this study.  
 
Introduction  
The introduction provides some good background, but overall is superficial. A more thorough 
review of the literature and citation of more current a nd geographically relevant sources would 
provide needed support to authors' claims; and it would give readers a better sense of what is 
already known and not yet known with confidence about the topic under examination in Nigeria.  
1. It would be beneficia l to add few sentences briefly summarizing the regional variations 
within the country in relation to the prevalence of IPV to give magnitude to the problem.  
 
2. Related to my comment in 1, the authors might need to provide information about the policy 
environment. Although, the Violence against Persons Prohibition Act (VPPA) in Nigeria 
frowns at IPV, there is tendency that flexibility of penal code (Section 55 (1) (d) in the 
Northern part of the country to beat wives for correctional purposes might have been fueling 
IPV in that region.  
 
3. P.5, line 9: The definition of "status" of women is vague. The concept is hard to define and 
depends on the society or family  view.  
 
4. The introduction has a limited conceptualization. Earlier epidemiologic studies have 
highlighted that some other factors such as family type (polygamous vs. monogamous), 
religion, marital status, age disparity, age of partnership, substance abus e and employment 
status of the male partners as indicators of IPV.   
 
5. As indicated in the title, the authors should specify some of the cultural norms that promote 
IPV. For instance, in cultures where bride price is paid, the male partners often use it a s an 
excuse to lay claims to ownership of their wives. Whereas in Tiv's culture (Northern 
Nigeria), beating one's wife is perceived as a sign of respect and love.  
 
Methods  
1. The study design is appropriate to meet the objectives.  
 
2. Although the survey wa s published in 2013, when was it conducted?  
 
3. P.7, line 10 -15: The authors stated, "Also, a subsample of one eligible woman per household 
was randomly selected to be asked additional questions regarding domestic violence." How 
did you define eligibility i n a polygamous setting?  
 
4. P.7, line 15 -19: "….. all men aged 15 -49 years who were either permanent residents of the 
households or visitors present in the households on the night before the survey were eligible 
to be interviewed." How many men were intervi ewed? How were they interviewed?  
 
5. For both the covariates and contextual factors: the variables assessed for this study were 
limited. As highlighted above, more predictors have been identified from literature. These 
factors could be potential confounding  factors.  
 
6. Clarification should be provided on the domain scores for the groups of questions. How are 
they calculated e.g. women status has 8 variables and each variable has various questions.  
 
7. What are the cut -off points for each categorization? E.g. Women status was categorized as 
low, middle and high; Community level control of female behavior (low, moderate and 
high) etc  
 
8. Please harmonize the eligibility criteria as regards to "ever -partnered" in P.7, line 31 and 
"age at marriage" on P.8, line 60.  What does "age at marriage" represent? Is for only those 
married women or did it include those in other relationships such as cohabitation?  
 
Results  
1. P.12, line 58 -60: state the absolute number before the percentages.  
 
2. Please what is the baseline cha racteristics of the men interviewed? This will add more to the 
context.  
 
3. P.14, table 1: age of respondents had many levels. Can some of the levels be merged to 
generate fewer levels?  
 
4. P.14, Table 1: The age range in the result "15 -49 years" is conflict ing with "15 -45 years" in 
the methods (P.9, line 29)  
 
5. P.17: Too much details on the random effects in the result section. Some of the narratives 
could be moved to methods.  
 
Discussion  
1. P.18, line 18: "…..but also by contextual factors such as men's att itude towards IPV at the 
community". It is difficult to conclude in this way since this analysis did not adjust for the 
effect of major confounders - substance abuse, ethnicity, sociodemographic characteristics of 
male partners, marital status, religion etc  
 
2. P.18, line 34 -35: "This prevalence was lower than the global lifetime prevalence of 30% 
from the WHO global and regional estimates of violence against women". This might be 
partly due to differential misclassification of outcome. Among the victims, the re is 
likelihood of denying any occurrence of IPV considering the consequences of voluntarily 
reporting such in their respective homes, with the possibility of their partners around. As 
stated in the methods that women were not allowed to proceed with the interview once 
privacy was breeched. However, this is still subjective.  
 
3. P.18, line 50 -52: "Women with higher status may be able to decide when and whom to 
marry, and thus they will be less likely to enter an abusive relationship in the first place". It 
seems the authors were trying to make a case for temporality. Due to the cross -sectional 
nature of the study, it is challenging to establish whether women's higher status preceded 
occurrence of IPV, or vice -versa.  
 
4. P.19, line 22 -31: women's age should no t be used as proxy for age of partnership. Age is not 
directly proportional to level of individual's maturity.  
 
5. P.19, line 57 -61: Beyond the community norms, men might feel threatened to lose control of 
their homes because of their wives higher social st atus and they might feel the only way to 
make them submissive is through IPV, even when the wives are still submissive. On the 
other hand, some women become disrespectful due to their social status leading to IPV.  
 
  
Format of references  
1. The applicants used the recommended Vancouver style.  
 
2. Please state the date of accessing the on -line materials.  
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
No 
 
Does the work include the necessary controls?  
If not, please specify which controls a re required in your comments to the authors.  
 
No 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your 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 qua lity 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  
organisation that may in any way gain or lose financially from the publication 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 publicati on of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently 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 decla re 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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