Abstract
Background
Witnessing inter-parental violence and bullying victimization is common for many children and adolescents. This study examines the role of witnessing inter-parental violence and bullying victimization in involvement in physical fighting among Peruvian adolescents.
Methods
A cross-sectional study was conducted among 1,368 randomly selected adolescents in 2015. We conducted logistic regression analyses to obtain crude and adjusted odds ratios with 95% confidence intervals for involvement in fighting among male and female adolescents.
Results
Among all adolescents, 35.8% had been involved in fighting in the last 12 months, 32.9% had been victim of verbal bullying and 37.9% had been the victim of physical bullying. Additionally, 39.2% and 27.8% of adolescents witnessed violence against their mother and father, respectively, at least once in their lives. Multivariate logistic regression analyses found that late adolescence, participation in economic activities, being the victim of verbal bullying, stress, and witnessing violence against the father among male adolescents, and self-rated academic performance and being the victim of physical or verbal bullying among female adolescents were associated with higher odds of being involved in fighting.
Conclusion
Verbal bullying victimization and witnessing violence against the father in males and bullying victimization in females were associated with greater odds of adolescents being involved in fighting. Creating a non-violent environment at both home and school would be an effective strategy for reducing fighting among the adolescent population.
Keywords: Fighting, Violence, Bullying, Adolescents, Peru
INTRODUCTION
Physical aggression among adolescents is increasingly being considered as a serious global issue rooted within multiple socio-environmental risk factors. One study based on data from 79 countries indicated that 30% of adolescents had reported bullying victimization, while 10.7% and 2.7% of males and females, respectively, were involved in frequent physical fighting [1]. Evidence suggests that a child witnessing violence is a contributing factor to aggressive behaviors, as well as psychosocial and academic difficulties [2–4]. Considering the apparent importance of this issue, a number of Sustainable Development Goals (SDGs) have been formulated to reduce rates of such violence. Specifically, SDGs target 16.1 and 16.2 state that it is necessary to reduce all forms of violence and all forms of violence against children, respectively, while SDG target 4.a refers to creating a non-violent, inclusive, and effective learning environment for individuals [5].
Maltreatment, abuse, and neglect among children under 18 years of age are global problems that have serious lifelong consequences for victimized children. Witnessing intimate partner violence can be similarly considered as a form of child maltreatment [6]. Witnessing violence at home can influence children’s physical and emotional well-being, behavior, cognitive and academic development, and social adjustment. These problems may contribute to an increased likelihood of children using violence in their own relationships [7]. Studies have shown that children who witness violence perpetrated by their parents are more likely to be involved in physical aggression compared with those who did not witness such violence [2,8]. Furthermore, witnessing inter-parental violence has diverse effects on adolescents, such as on adolescent self-perceived health, satisfaction with life, family relationships, and involvement in school bullying [4]. Bullying is a broad term that varies notably among cultures, although it most often comprises physical violence, verbal violence, or social exclusion [9]. Notably, sibling violence occurs more frequently than does other forms of child abuse, and is significantly related to higher rates of delinquency and aggression [10]. Furthermore, bullying victimization has been found to be positively associated with violent behavior, whereas helpful peers and understanding parents are negatively associated with such behavior [11].
Fighting, bullying, and bullying victimization are serious problems among in-school adolescents in Latin American countries [12–15]. Furthermore, the results of a Demographic Health Survey indicated that, in Peru, 38.9% of women have been physically abused by their intimate partners [16]. Bullying victimization among adolescents was found to be associated with significant emotional and mental stress [17]. In addition, involvement in fights and being physically attacked were associated with higher rates of suicidal ideation and suicide attempts among adolescents [18].
Based on the above background, we hypothesized that witnessing inter-parental violence and physical and verbal bullying victimization would be related to involvement in fighting among adolescents. As evidence indicated that male adolescents are more likely to be involved in physical fighting [13,14,19,20], we analyzed the effects of the independent variables on involvement in fighting separately for male and female adolescents. Thus, the study aimed to assess the role of witnessing inter-parental violence and bullying victimization in involvement in fighting among Peruvian adolescents.
MATERIALS AND METHODS
1. Study setting, design and sampling
This study utilized information collected as a health survey among secondary school students in Lima, Peru. The survey was performed by Yonsei Global Health Centre in November 2015, collaborating with the Korea International Cooperation Agency (KOICA), Peru Office. This cross-sectional survey was conducted with a sample of 1,368 Peruvian secondary school students. The first sampling unit was six public high schools located in Comas and Callao. Then, we used stratified random sampling to select participants from the 4,462 students across these six schools. The stratified unit (classroom) was determined for each school, and students were selected using systematic selection with random start from each stratum. A total of 1,377 students were randomly selected; nine students were excluded from the analyses because of incomplete information. Thus, 1,368 participants were analyzed for the study.
2. Data collection and measurement
Participants completed an anonymous self-report questionnaire assessing their socio-demographic variables and the various violence-related variables, including involvement in fighting, witnessing inter-parental violence, and experience of bullying victimization. Questionnaires were administered to the selected students in their classrooms by trained enumerators. Enumerators provided a brief orientation on the objective of the study and ways of providing responses before completing the questionnaire. Table 1 provides the information on the measurements of variables used in the study. The dependent variable was involvement in fighting. Five sociodemographic variables, three variables related to violence victimization and stress, and six variables related to witnessing inter-parental violence were analyzed in this study. Family economic status was assessed by asking adolescents about their perception of this status. Although this is not a precise method for determining economic status, it does provide a rough indicator. Regarding physical bullying perpetration for siblings and others, we removed the response options of “do not want to answer” or “do not remember” from the analysis to make the dependent variable dichotomous. We similarly removed the “do not remember” option from the items assessing witnessing inter-parental violence and violence victimization.
Table 1.
Measurement of variables
| Variables | Categorization | Question asked |
|---|---|---|
| Sociodemographic | ||
| Sex | Male | What is your sex? |
| Female | ||
| Age | 11–14 years | How old are you? (in years) |
| 15–19 years | ||
| Participation in economic activity | Yes | Are you participating in any activity that helps to earn money for your family, personal expenses or any other end, after school? |
| No | ||
| Perceived economic status | High | What is your family’s economic status? |
| Above average | ||
| Average | ||
| Below average | ||
| Low | ||
| Self-reported academic performance | High | In the last 12 months, how would you rate your academic performance? |
| Above average | ||
| Average | ||
| Below average | ||
| Low | ||
| Involvement in fighting | ||
| Involvement in fighting | None | In the last 12 months, how many times were you involved in a physical fight? (frequency was measured) |
| Once or more | ||
| Violence victimization and stress | ||
| Physically bullied | Yes | Has someone ever beaten, slapped, kicked, or otherwise physically mistreated you? |
| No | ||
| Verbally bullied | None | In the last 30 days, how many times were you intimidated or humiliated? |
| Once or twice | ||
| Three times or more | ||
| Stress level | Too much/much | In general, what is your level of stress? (too much, much, little, very little, or none) |
| Little | ||
| Very little/none | ||
| Witnessing inter-parental violence | ||
| Physical violence against mother | Yes | As far as you know, has your father ever beaten, slapped, kicked, or otherwise physically mistreated your mother? |
| No | ||
| Verbal violence against mother | Yes | As far as you know, has your father ever insulted/offended or otherwise verbally disrespected your mother? |
| No | ||
| Physical violence against father | Yes | As far as you know, has your mother ever beaten, slapped, kicked, or otherwise physically mistreated your father? |
| No | ||
| Verbal violence against father | Yes | As far as you know, has your mother ever insulted/offended or otherwise verbally disrespected your father? |
| No | ||
| Violence against mother | Yes | Physical, verbal, or both (derived from questions on physical and verbal violence) |
| No | ||
| Violence against father | Yes | Physical, verbal, or both (derived from questions on physical and verbal violence) |
| No | ||
3. Data analysis
Data were entered, cleaned, and analyzed using SPSS for Windows, version 21 (IBM Corp.: Armonk, NY, USA). A frequency distribution was prepared for the dependent and all the independent variables. Then, a bivariate analysis was performed to determine the relationships between the dependent variable and all the independent variables, both for the total sample and for male and females, separately. Multivariate logistic regression analyses were performed, separately by gender, including the variables that were significant in the bivariate analyses as shown in the Fig. 1. The significance level was set at 5% for both the bivariate and multivariate analyses. Before computing the binary logistic regression models, we assessed the correlations among the independent variables and the goodness of fit of the model. The effect of multicollinearity in the model was checked using variance inflation factors; however, no effect was observed. As the Hosmer–Lemeshow test result was not significant (>0.05), the model was considered to fit the variables well.
Fig. 1.
Analysis model for involvement in fighting.
4. Ethical considerations
Ethical approval for this study was obtained from the Institutional Review Board of Wonju Campus, Yonsei University (1041849-201410-BM-048-02) and the DIRESA Callao (local government of Peru). Prior consent was obtained from each school and parents or guardians. Informed assent was obtained from individual participants, and an anonymous questionnaire was used.
RESULTS
Table 2 shows that out of the total respondents. 61.6% were female and 38.4% were male; 55.3% and 44.7% were in their early and late adolescence, respectively. Approximately three-fifths of the respondents (61.7%) reported that they were from a family of average economic status, 76.6% of adolescents participated in some kind of economic activity after school and almost half (48.4%) reported that their academic performance was average. With regard to violence-related variables, 35.8% of adolescents had been involved in fighting one or more time in the last 12 months. In total, 32.9% had been verbally bullied at least once in the last 30 days, and 37.9% had been victims of physical bullying; 27.5% reported they experienced much stress. In addition, 27.7% and 38.5% of respondents reported having witnessed their fathers engaging in physical and verbal violence, respectively, against their mothers. Similarly, 16.5% and 26% of respondents reported witnessing their mothers engaging in physical and verbal violence, respectively, against their fathers. In total, 39.2% and 27.8% of respondents had witnessed physical, verbal, or both types of violence against their mothers and fathers, respectively, in their lives.
Table 2.
Characteristics of the study population
| Variables | n | % |
|---|---|---|
| Sociodemographic | ||
| Sex | ||
| Male | 525 | 38.4 |
| Female | 843 | 61.6 |
| Age group | ||
| 11–14 years | 756 | 55.3 |
| 15–19 years | 612 | 44.7 |
| Participation in economic activity | ||
| Yes | 1042 | 76.6 |
| No | 319 | 23.4 |
| Perceived economic status | ||
| High | 96 | 7.0 |
| Above average | 274 | 20.1 |
| Average | 841 | 61.7 |
| Below average | 119 | 8.7 |
| Low | 32 | 2.3 |
| Self-reported academic performance | ||
| High | 169 | 12.4 |
| Above average | 312 | 22.9 |
| Average | 659 | 48.4 |
| Below average | 157 | 11.5 |
| Low | 64 | 4.7 |
| Involvement in fighting | ||
| One or more times | 487 | 35.8 |
| None | 875 | 64.2 |
| Violence victimization and stress | ||
| Verbally bullied | ||
| None | 904 | 67.1 |
| 1 or 2 days | 305 | 22.6 |
| 3 or more days | 139 | 10.3 |
| Physically bullied | ||
| Yes | 453 | 37.9 |
| No | 742 | 62.1 |
| Stress | ||
| Very little/none | 491 | 36.0 |
| Little | 497 | 36.5 |
| Too much/much | 374 | 27.5 |
| Witnessing inter-parental violence | ||
| Physical violence against mother | ||
| Yes | 341 | 27.7 |
| No | 891 | 72.3 |
| Verbal violence against mother | ||
| Yes | 467 | 38.5 |
| No | 746 | 61.5 |
| Physical violence against father | ||
| Yes | 202 | 16.5 |
| No | 1025 | 83.5 |
| Verbal violence against father | ||
| Yes | 314 | 26.0 |
| No | 892 | 74.0 |
| Violence against mother | ||
| None | 700 | 60.8 |
| Verbal or physical | 162 | 14.1 |
| Both physical and verbal | 289 | 25.1 |
| Violence against father | ||
| None | 833 | 72.2 |
| Verbal or physical | 169 | 14.7 |
| Both physical and verbal | 151 | 13.1 |
As shown in Table 3, male early adolescents were less likely to be involved in fighting compared with male late adolescents. However, we found no association between age and involvement in fighting among female adolescents. Similarly, self-perceived economic status had no association with involvement in fighting among either sex. However, we found that involvement in economic activity after school had a significant association with the odds of being involved in fighting in the total sample as well as among both sexes; specifically, those involved in economic activity had greater odds of being involved in fighting. Individuals with higher self-reported academic performance were less likely to be involved in fighting, but only among female adolescents. Physical and verbal bullying victimization were both associated with higher odds of being involved in fighting. Similarly, both male and female adolescents with higher stress levels had greater odds of involvement in fighting. Both physical and verbal violence against the mother or father were associated with greater odds of being involved in fighting among male adolescents; this same pattern was observed among female adolescents, except for physical violence against the mother, which was non-significantly related to the odds of involvement in fighting.
Table 3.
Crude odds ratios for involvement in fighting according to the results of a logistic regression analysis
| Variables | COR (95% CI) | ||
|---|---|---|---|
|
| |||
| Total | Male | Female | |
| Sociodemographic | |||
| Sex | |||
| Male | 3.67 (2.90–4.63)*** | - | - |
| Female | 1 | - | - |
| Age group | |||
| 11–14 | 0.87 (0.70–1.09) | 0.66 (0.46–0.93)* | 0.85 (0.62–1.18) |
| 15–19 | 1 | ||
| Participation in economic activity | |||
| Yes | 1.91 (1.48–2.47)*** | 1.78 (1.21–2.61)** | 1.53 (1.04–2.24)* |
| No | 1 | ||
| Perceived economic status | |||
| High/above average | 0.93 (0.63–1.39) | 1.18 (0.60–2.33) | 0.66 (0.39–1.11) |
| Average | 1.03 (0.72–1.49) | 1.22 (0.65–2.29) | 0.752 (0.474–1.19) |
| Below average/poor | 1 | 1 | 1 |
| Self-reported academic performance | |||
| High/above average | 0.62 (0.45–0.86)** | 1.04 (0.60–1.78) | 0.36 (0.23–0.56)*** |
| Average | 0.64 (0.47–0.87)** | 0.81 (0.48–1.35) | 0.48 (0.32–0.72)*** |
| Below average/poor | 1 | 1 | 1 |
| Violence victimization and stress | |||
| Verbally bullied | |||
| 1–2 days | 2.19 (1.67–2.86)*** | 2.31 (1.46–3.64)*** | 2.94 (2.03–4.26)*** |
| ≥3 days | 3.52 (2.44–5.09)*** | 4.24 (1.98–9.08)*** | 5.11 (3.21–8.12)*** |
| None | 1 | 1 | 1 |
| Physically bullied | |||
| Yes | 2.34 (1.83–2.98)*** | 2.46 (1.63–3.71)*** | 3.13 (2.22–4.42)*** |
| No | 1 | 1 | 1 |
| Stress | |||
| Too much/much | 1.64 (1.23–2.18)** | 2.47 (1.47–4.15)** | 2.34 (1.56–3.51)*** |
| Little | 1.55 (1.18–2.02)** | 1.53 (1.04–2.24)* | 1.68 (1.11–2.56)* |
| Very little/none | 1 | 1 | 1 |
| Witnessing inter-parental violence | |||
| Physical violence against mother | |||
| Yes | 1.18 (0.91–1.53) | 1.87 (1.17–3.01)** | 1.28 (0.90–1.81) |
| No | 1 | 1 | 1 |
| Verbal violence against mother | |||
| Yes | 1.38 (1.08–1.76)** | 2.19 (1.43–3.35)*** | 1.66 (1.18–2.32)** |
| No | 1 | 1 | 1 |
| Physical violence against father | |||
| Yes | 1.54 (1.13–2.09)** | 3.19 (1.69–6.015)** | 1.52 (1.02–2.28)* |
| No | 1 | 1 | 1 |
| Verbal violence against father | |||
| Yes | 1.45 (1.11–1.89)** | 2.22 (1.36–3.63)** | 1.68 (1.18–2.39)** |
| No | 1 | 1 | 1 |
p < 0.001,
p < 0.01,
p < 0.05.
Table 4 shows the adjusted odd ratios (AORs) for involvement in fighting among male and female adolescents according to the various sociodemographic and violence related variables. Early adolescent respondents had lower odds of being involved in fighting relative to those in late adolescence (AOR 0.58, CI 0.36–0.94), and participation in economic activity after school was significantly associated with greater odds of being involved in fighting only among male adolescents (AOR 2.29, CI 1.36–3.83). Self-reported academic performance remained significantly associated with fighting among female adolescents in the adjusted model. Physical and verbal bullying victimization among female adolescents and verbal bullying victimization among male adolescents were associated with greater odds of being involved in fighting. Male and female adolescents who had been verbally bullied three or more times in the last 30 days had a 3.8 and 4.7 times greater odds, respectively, of being involved in fighting as compared to those who had not been verbally bullied. Female adolescents who were victims of physical bullying also had greater odds of being involved in fighting (AOR 2.41, CI 1.53–3.82). Male adolescents who witnessed violence (both verbal and physical) against their father had greater odds of being involved in fighting (AOR 2.98, CI 1.10–8.04). In addition, stress levels also had a significant association with fighting among male adolescents.
Table 4.
Adjusted odds ratios for involvement in fighting among male and female adolescents
| Variables | AOR (95% CI) | |
|---|---|---|
|
| ||
| Male | Female | |
| Sociodemographic variables | ||
| Age group (in years) | ||
| 11–14 | 0.58 (0.36–0.94)* | - |
| 15–19 | 1 | |
| Participation in economic activity | ||
| Yes | 2.29 (1.36–3.83)** | 1.03 (.62–1.72) |
| No | 1 | |
| Self-reported academic performance | ||
| High/above average | - | 0.37 (0.20–0.68)** |
| Average | - | 0.518 (0.29–0.90)** |
| Below average/low | 1 | |
| Violence victimization | ||
| Verbally bullied | ||
| 1–2 days | 1.67 (0.93–2.99) | 2.76 (1.67–4.55)*** |
| ≥3 times | 3.82 (1.22–11.96)* | 4.78 (2.57–8.88)*** |
| None | 1 | 1 |
| Physically bullied | ||
| Yes | 1.60 (0.947–2.708) | 2.41 (1.53–3.82)*** |
| No | 1 | 1 |
| Stress | ||
| Too much/much | 2.33 (1.11–4.89)* | 1.03 (0.59–1.81) |
| Little | 1.48 (0.89–2.45)* | 1.16 (0.68–1.99) |
| None/very little | 1 | 1 |
| Witnessing inter-parental violence | ||
| Violence against mother | ||
| Physical or verbal | 0.62 (0.27–1.39) | 1.34 (0.72–2.50) |
| Both physical and verbal | 1.15 (0.54–2.44) | 1.07 (0.61–1.87) |
| None | 1 | 1 |
| Violence against father | ||
| Physical or verbal | 1.43 (0.64–3.23) | 1.08 (0.58–2.00) |
| Both physical and verbal | 2.98 (1.10–8.04)* | 0.93 (0.496–1.74) |
| None | 1 | 1 |
p < 0.001,
p < 0.01,
p < 0.05.
DISCUSSION
The magnitude of involvement in fighting in the study area (35.8%) was similar to the finding of the Global School-based Student Health Survey conducted in 2010 in Peru (37.8% and, 52.9% of male and 22.2 of female) [21]. Furthermore, being victims of physical and verbal bullying and witnessing inter-parental violence were both common. More specifically, 32.9% had been verbally bullied one or more times in the last 30 days, and 37.9% had been physically bullied in the last 12 months, a finding very similar to the national average found in the Global School-based Student Health Survey in Peru (37.8%) [21].
In a previous study, 40.7% of Chilean adolescents reported having been involved in a physical fight in the 12 months prior to the study; furthermore, male adolescents were more likely to have been involved in a physical fight than were female adolescents, consistent with the present study and Peruvian Global School-based Student Health Survey [14,21]. These rates were higher in Namibia, where 50.6% reported having been involved in a physical fight in the past 12 months, with males being more vulnerable than females [22]. Male adolescents younger than 15 years old were less likely to be involved in fighting in this study. In contrast, US adolescents aged 17 years or older were less likely to report physical fighting than were those aged 14 years or younger [23]. In the current study, female adolescents with higher self-reported academic performance were less likely to be involved in fighting; however, no such association existed among male adolescents. Among both genders, a statistically significant association was found between physical fighting and grade retention among Portuguese adolescents [19]. Similarly, a study in 16 Latin American countries found that students who suffered from peer victimization had significantly lower academic performance [12].
We also found that being a victim of verbal bullying was significantly associated with fighting between both sexes; however, physical bullying victimization was significant only among female adolescents. Bullying victimization was also found to be positively associated with involvement in fighting among adolescents from Chile, Malaysia, Egypt, and the US [11,14,23,24]. Furthermore, a dose-response relationship between bullying victimization and physical fighting has been found [13], which indicates that the more frequent the bullying, the more the aggressive behavior.
We measured witnessing of inter-parental violence separately by parent (i.e., violence against the mother or the father), and found that witnessing verbal and physical violence against the mother was more frequent (39.2% and 27.8%, respectively) than was witnessing such violence against the father (16.5% and 26%, respectively). These results are in accord with those of another study in Italy [8]. More than half of secondary school students witnessed domestic violence between their parents in a study conducted in Iran [25]. However, perhaps the most interesting finding of the study was that violence against the mother was not significantly associated with increased odds of involvement in fighting or in physical bullying perpetration in either sex in an adjusted model. A study by Baldry et al. in Italy found that witnessing a mother’s violence against the father significantly predicted bullying among adolescents [8]. We also found that violence against the father was associated with significantly greater odds of involvement in fighting among male adolescents. This may be because violence against women has been accepted by both genders as normal. However, further studies are required to investigate the reasons why witnessing violence against fathers and mothers have differential effects on involvement in fighting. We also found that higher level of stress among male adolescents was associated with higher odds of being involved in fights. Depressive symptoms were positively associated with violent behavior in Egypt [11]. Our results indicate that the prevention of violent behavior among adolescents should involve ensuring a violence-free environment both at home and school. Family, peer, and school social environments have been found to serve as both risk and protective factors that have significant cumulative effects on physical aggression [19,26]. Involvement in fighting among adolescents in the study area was similar to the national average of Peru; male adolescents were more likely to fight relative to females. Late adolescence, participation in economic activities after school, being victims of verbal bullying, stress and witnessing inter-parental violence against the father were significantly associated with greater odds of involvement in fighting among male adolescents. Self-reported poor academic performance and being a victim of physical and verbal bullying were associated with greater odds of involvement in fighting among female adolescents. Based on the findings of the study, to prevent the fighting among adolescents, interventions should focus on late adolescence, reducing verbal bullying victimization, stress and inter-parental violence against father for males, and minimizing physical and verbal bullying victimization for females. Involvement of parents in school health education programs may contribute to reduce inter-parental violence and adolescent bullying victimization. In the study area, creating a non-violent environment for children and adolescents at home and school is essential.
ACKNOWLEDGEMENTS
We appreciate the support of the Korea International Cooperation Agency (KOICA). We express our special thanks to the study participants, school staff, field enumerators, and all other partners in Peru who made this survey possible. We also express our sincere gratitude to Dr. Miguel Malo, Advisor in non-communicable disease and sustainable development and health, PAHO/WHO Peru office.
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