Reviewer ’s report  
 
Title: Aggressive behavior among drug -using women from Cape Town, South Africa: ethnicity, 
heavy alcohol use, methamphetamine and intimate partner sexual violence  
 
Version: 0 Date: 13 Jan 2017  
 
Reviewer: Mekeila Cook  
 
Reviewer's r eport:  
 
Review of manuscript: BMWH -D-16-00282 entitled, "Ag gressive behavior among drug -using 
women from Cape Town, South Africa: ethnicity, heavy alcohol use, methamphetamine and 
main partner sexual violence".  
This paper addresses an important public health concern by tackling an under -studied area of 
violence perpetration by women. The authors seek to explore factors related to aggression 
(defined as verbal, physical, or use of a weapon). The main factors examined were age, ethnicity, 
substance use, and main sexual partner violence. Given the important topical nature of this study, 
there were a number of theoretical and methodological concerns that need to be addressed.  
The introduction at times seems a bit disjointed. Take the following excerpt for example: "For 
example, studies have shown that women are beco ming increasing verbally aggressive (16) and 
violent (17) in relationships, in response to interpersonal violence from their male partner (18). 
In these settings, substance -using women have been found to engage in both physical and verbal 
aggression (19, 2 0).Furthermore, there is emerging evidence that women who self -identify as 
gang members engage in physically violent behaviours, such as fighting with weapons (21)." 
Does "in these settings" refer to experiencing intimate partner violence? Also, does this 
statement only apply to substance -using women who engaged in aggression with a male partner 
who has been violent towards them? This statement needs to be further unpacked. Are the 
authors suggesting that the aggression substance -using women are exhibiting towards their male 
partner is due to the woman's use of alcohol and drugs? Are the authors suggesting that the 
aggression substance -using women are exhibiting towards their male partner is in response to 
violence perpetrated by the partner? These points ne ed to be clarified. Additionally, the next 
sentences proposes that aggression in women is associated with being a gang member but there 
is no context provided with this statement and the authors do not provide an explanation of how 
gang -membership ties int o the current study.  
 
Theoretical Concerns:  
On page 5 the authors state: "This paper aims to address this gap through describing aggressive 
behaviour among substance -using women in Cape Town, South Africa and exploring potential 
factors associated with v erbal, physical and weapon -using aggression among substance -using 
women." The authors do not provide a rationale for choosing the factors included in the analysis. 
Furthermore, the authors do not provide hypotheses for what they expected to find. Given the  
exploratory nature of the study, the paper would greatly benefit from the inclusion of a 
theoretical framework to guide the study.  
 
Methodological Concerns:  
More detail on the sampling design needs to be provided. The authors offer the following 
sentenc e: "Outreach workers visited each communities and marketed the study with flyers, and 
spoke to women who were possibly eligible." How did the outreach workers market with flyers? 
Did they post fliers somewhere? Were flyers handed out directly to people? Fu rthermore, were 
there targeted areas that outreach workers visited like markets, schools, hair salons, etc.?  
Approximately how long did the interview take participants to complete?  
There needs to be more details provided on the measurements used in the  study. What is the 
reliability score of the Revised Risk Behaviour Assessment? Being that the authors featured 
certain demographic factors in their analysis more details about these factors need to be 
provided. For example, what is the length of time asse ssed for unemployment (currently 
unemployed, 3 months unemployed, 6 months, etc.)? How was income assessed? For educational 
attainment, did the authors control for women who were currently enrolled in school and had not 
yet completed high school? Are the e thnic categories limited to only Black and "Coloured" 
women?  
A more thorough description of the interpersonal violence questions needs to be included in the 
measures section. A related recommendation is to move the following description from page 7 to 
the measures section: "frequency of drinking, cannabis use and methamphetamine use in the past 
30 days, and main sex partner violence in the past six months on verbal, physical and weapon 
aggression in the past 90 days…"  
A description of how the Conflict Ta ctics Scale is scored is needed.  
 The Results section needs more development. In the section on substance use and intimate 
partner violence, the authors report women with a higher average meth use were more likely to 
report the 3 types of aggression. Wha t is considered a "higher average"? The entire results 
section needs to be re -written to provide context to the numbers presented. For example, 
presenting the mean and range of meth use in the past 30 days would provide context to the 
reader so when the au thors present Chi -Square results the reader will have a base from which to 
compare. This can be easily addressed by presenting a table with simple summary and 
descriptive univariate statistics for each variable of interest.  
Under the multivariate analysis section, the authors need to add an introductory sentence 
summarizing which analysis they are using and specifically naming the factors included in the 
analysis.  Stating "other possible confounding variables" is unclear. As  stated above, "heavy 
drinking" needs to be quantified and defined.  
The current study seems to present substance use and aggression in one regression model and 
aggression and main partner violence in another regression model. It would seem that substance  
use by the participant may account for some of the variance observed between aggression and 
main sexual partner violence. A recommendation is to run a regression that includes main sexual 
partner violence, aggression and substance use in a model together.   
 
Discussion section  
The following statements needs to be developed more:  
On page 9, "Our findings show that an unexpectedly high proportion of substance -using women 
engaged in recent acts of aggression." First, in reference to "unexpectedly high propor tion"; it is 
difficult to understand what the authors expected to see when hypotheses are not presented.  
On page 9, "This is a concerning trend as it may increase their risk for violence against them as 
previous studies indicated and may perpetrate cycle s of substance use and violence towards 
women that are often experienced in these communities." What is a concerning trend? That 
women use substances or that women reported recent aggression? The statement about cycles of 
substance use needs to be unpacked ; for example, why would their aggression lead to more 
violence victimization? There are a number of theoretical frameworks that address the 
relationships between substance use, violence perpetration and violence victimization. The 
authors need to provide more detail and explanation on this point.  
On page 10, the authors write: "… there is also evidence that violence against women is inter -
generationally transmitted, especially domestic violence". This is a new theory that is not 
previously discussed in t he Introduction. The authors do not provide context about how inter -
generational violence may be associated with aggression among substance -using women. The 
point raised by the authors requires more explanation.  
On page 10 the authors appear to link the finding of a positive association between ethnicity and 
verbal aggression with gang -activity. Although studies are referenced in the Introduction, the 
authors should take extreme caution in the manner in which they draw conclusions. Being that 
gang affilia tion was not assessed in the current study, this statement is a gross over -
simplification of the findings. If the authors plan to offer gang affiliation as a possible reason for 
the association between ethnicity and verbal aggression, the authors will need  to address the 
socio -cultural implications for gang -affiliation and would likely need to include a discussion on 
racial and ethnic inequity, segregation and other structural factors that may contribute to this 
finding.  
On page 10, the authors report tha t there was not a statistically significant difference between 
heavy alcohol use and physical aggression. I assume the authors expected to find an association? 
The authors do not offer an explanation or possible reason as to why they did not find a 
relatio nship.  
On page 12, the authors state "In South Africa, there are many barriers to substance -using 
women accessing mental health services that include trauma support (29). Trauma -informed 
substance use services are needed for women to prevent the progress ion of substance use as well 
as violent behaviour." The authors do not discuss the barriers to treatment women face in South 
Africa. A discussion on these barriers could lend to policy and practice -based suggestions.  
 
General Concerns and Suggestions:   
In the first paragraph of the Introduction, the authors refer to prevalence rates for homicides but 
do not provide numbers. It would be helpful to readership outside of South Africa to have 
numbers to better understand the national and global average of hom icide rates that are being 
compared.  
Is there a specific reason the authors use the term "main sexual partner violence" as opposed to 
intimate partner violence? Given the rich body of work that has been published on intimate 
partner violence, the authors  may need to provide rationale for using the term "main sexual 
partner violence" in the measures section.  
In reference to the aggression measure, the authors do not provide information about the 
relationship between the participant and the victim.  Was t here a question on the survey to assess 
relationship? If not, this should be included as a limitation of the study. The omission of details 
about the relationship becomes magnified in the Discussion section when the authors are 
discussing the relationship between aggression and male partner violence. It is unclear as to 
whether the aggression the participant reports is within the context of experiencing intimate 
partner violence or if the participant expresses aggression towards someone other than her 
intim ate partner but also happens to experience main sexual partner violence.  
 
Tables:  
Table 1 is very difficult to read and understand; it needs to be formatted so that a complete word 
appears on a single line. Consider creating table in the landscape orient ation setting.  
 
Provide a caption for terms in the table. For example, "Emerging adult" = ages XX -ZZ  
Add a space between numbers and parenthesis. For example, 5.79 (2)  
 
Minor Concerns:  
On page 10, the authors state: "A possible reason was that the age range of the sample was 
restricted, with all participants being under 35 years old." On page 5 the authors state the age 
range is 18 -33.  
Need citation for the following statement: Previou s studies have also shown that there is indeed a 
long history of violence in the Western Cape.  
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 are required in your comments to the authors.  
 
Unable to assess  
 
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 s tatistical 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 o r 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 publication of this manuscript, either now or in the futur e? 
 
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 t he manuscript?  
 
5. Do you have any other financial competing interests?  
 
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below.  If your reply is yes to any, please give details below.  
 
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