Bullying Victimization in Brazilian Schoolchildren and its Impact on Oral Health-Related Quality of Life: A Population-Based StudyABSTRACT
Objective: To assess whether the quality of life related to oral health is impacted by the presence of bullying in Brazilian schoolchildren.
Material and Methods: This cross-sectional study was conducted in a municipality in the state of Paraíba, Brazil, and included 461 schoolchildren aged 12-15 years. To characterize the socioeconomic and family context, a questionnaire aimed at parents/caregivers was used. Bullying was assessed using the Olweus Bullying Questionnaire (OBQ) (victim version). Oral health-related quality of life (OHRQoL) was measured by the Oral Health Impact Profile (OHIP-14) and dichotomized into two groups: impact or no impact. Descriptive statistics were used, and the analysis of characteristics associated with bullying victimization and OHRQoL was performed using Pearson's chi-square test.
Results: The prevalence of bullying victimization was 35.8%, with emphasis on verbal perpetration. Victimization was not associated with gender or age group, but was associated with dental bullying (p<0.001). For 49.9% of adolescents, there was an impact on oral health-related quality of life, with the “psychological discomfort” domain being the most affected. OHRQoL was associated with bullying victimization (p<0.001).
Conclusion: A high proportion of elementary school students are victims of bullying, and verbal insults are the main modality used by their peers. Impact on students' quality of life was observed, above all, by psychological suffering and losses in social interaction.
Keywords:
Adolescent Behavior; Bullying; Violence; Quality of Life.
Introduction
Bullying in schools is currently recognized as one of the main challenges to the health and well-being of adolescents, being identified as a global public health problem with lasting effects on the physical, psychological, and social health of this population [1]. Victims of bullying often report experiencing feelings of loneliness, depression, stress, anxiety, and suicidal thoughts [2,3]
A global estimate of the problem, from a comprehensive meta-analysis [4], indicates that 1 in 4 adolescents is a victim of bullying. Even so, there are discrepancies in its prevalence, which can be attributed to methodological characteristics of studies [5] and sociocultural and contextual variations across populations [2,6], with bullying frequencies ranging from 16.2% [7] to 78% [8].
In addition to individual characteristics and socioeconomic factors, oral health status can be used as a trigger for bullying, perpetuating, on some occasions, the cycle of bullying occurrence through provocations, humiliation, and even physical violence, which significantly affects school performance [9-11].
Previous studies have associated the implication of this type of aggression with oral health-related quality of life (OHROoL), finding high scores and negative impacts on the lives of schoolchildren [12-14]. In a recent prospective cohort study conducted in China, Wang et al. [15] demonstrated that adolescents who reported bullying experiences at baseline were more likely to have worse OHRQoL at follow-up, demonstrating a longitudinal association between the phenomena. The authors found that both victims and, even more significantly, bully-victims (individuals who both suffer and perpetrate bullying) presented greater impairment in quality of life, especially in the domain of social well-being. These findings indicate that the impact of bullying goes beyond the immediate effects, contributing to sustained negative consequences for adolescents' oral health and psychosocial well-being [15].
Therefore, the information presented above highlights the need for a greater understanding of the impact of bullying victimization on OHRQoL, especially in countries like Brazil, where malocclusion, untreated caries lesions, and tooth loss are common and directly associated with bullying [16,17]. In this context, the objective of this study was to estimate the prevalence of bullying victimization among Brazilian schoolchildren and assess its impact on oral health-related quality of life.
Material and Methods
Scenario
A cross-sectional epidemiological study was conducted in the municipality of Campina Grande, located in the interior of the state of Paraíba, Brazil. This municipality boasts a Human Development Index (HDI) of 0.72 and a Gini Index of 0.58. With a population of 419,000 residents, it also has a school enrollment rate of 97.6% for students aged 6 to 14 years, supported by a total of 288 elementary schools [18].
Sampling
A total of 53,114 students were enrolled in all elementary schools. The sample was calculated considering a prevalence of 50% and a confidence level of 5%. A design effect of 1.2 was used, resulting in a sample of 461 students, distributed across six educational institutions in the municipal network. The sampling process was carried out in two stages: in the first, schools were randomly selected; in the second, eligible students were selected.
Participants
Students of both genders aged 12 to 15 years who were regularly enrolled in the elementary cycle were deemed eligible for participation. However, schoolchildren who experienced difficulties comprehending the requirements of the data collection instruments, even with assistance from the researchers, were excluded from the sample. Additionally, those absent for health reasons were also not included.
Data Collection
The individual variables, socioeconomic and family context characterization of students included: sex (male/female), age group (12-13 years/14-15 years), ethnicity (white/non-white), maternal schooling (≤ 8 years of study/> 8 years of study) monthly income (up to 1 minimum wage/more than 1 minimum wage), Bolsa Família benefit (yes/no) and type of housing (owned/rented/provided). The Bolsa Família program is a conditional cash transfer program, created in 2003, to improve health outcomes, reduce poverty, and increase food security.
To assess bullying victimization, the Olweus Bullying Questionnaire (OBVQ) - victim version was used [19]. Therefore, for this study, students who selected the option “several times a week” in at least one of the 23 questionnaire items were classified as victims [20]. According to the answers, students were subdivided into three groups, which reflect the types of bullying occurrence: G1) Direct physical bullying (9 OBVQ items - 1, 2,4, 5, 6, 14, 15, 16, 22); G2) Direct verbal bullying (8 OBVQ items - 3, 7, 8, 9, 10, 11, 12, 13); and G3) Indirect bullying (6 OBVQ items - 17, 18, 19, 20, 21, 23). Additionally, questions about dental bullying (yes/no) and the reasons for its occurrence were included.
In the Oral Health-Related Quality of Life (OHRQoL) analysis, the Oral Health Impact Profile (OHIP-14) [21] was used. The questions are subdivided into seven conceptual domains: 1. Functional Limitation, 2. Physical Pain, 3. Psychological Discomfort, 4. Physical Disability, 5. Psychological Disability, 6. Social Disability and 7. Handicap. Each question has a specific weight, so that each dimension reaches a maximum value of 4, with the total score ranging from 0 to 28 [21].
The data collection process occurred from April to June 2023 and involved a team of six researchers. Information regarding individual, socioeconomic, and family contexts was gathered through a questionnaire administered to parents and caregivers. Additional research instruments were distributed to students within the educational institutions.
Data Analysis
Data were analyzed using the Statistical Package for the Social Sciences software (SPSS for Windows, version 24.0, IBM Corp., Armonk, NY, USA). Descriptive statistics were performed, and the Pearson's Chi-square test was used to assess possible associations between bullying and the independent variables. Bivariate analyses were conducted considering “bullying victimization” and “OHIP-14” as the outcome. When analyzed as a categorical variable, OHIP-14 was classified into two groups. Group 1 (G1) was considered to have no impact when response options were “sometimes”, “rarely”, and “never”. Group 2 (G2) was considered to have an impact when the response options were “often” and “always”. The same criterion was used for each of the seven domains; therefore, if the student declared impact on at least one item in the dimension, it was considered to have an impact.
Ethical Clearance
The study was approved by the Research Ethics Committee of the State University of Paraíba, under number 4,974,026. Parents and guardians provided consent by signing the Informed Consent Form, while schoolchildren provided assent by signing the Free and Informed Assent Form.
Results
There was a balance in the distribution of participants by sex, with a slight predominance of females (50.1%), and by age, with a slight predominance of students aged 12-13 years (67.0%). White students accounted for 25.3% of the sample. Regarding the family context, it was found that mothers had more than eight years of study (58.8%), monthly earnings amounted to up to one minimum wage (62.2%), the Bolsa Família cash transfer program was granted in 52.5% of cases, and 59.2% of students lived in their own homes (Table 1)
The prevalence of bullying victimization was 35.8% (n=165). Regarding the type of bullying, for “Physical bullying”, there was a predominance of situations involving hair pulling and scratching (15.8%). In “Verbal bullying” and “Indirect bullying”, categories, swearing (44.5%) and the action “They made or tried to make others dislike me” (29.7%) were commonly reported (Table 2).
Among the 165 victimized students, harassment due to dental reasons affected 43.3% (n=71). Dental positioning was identified as the main reason for the occurrence of this event. Table 3 presents the bivariate analysis of bullying victimization by sex, age group, and dental bullying occurrence. Victimization was associated with episodes of dental bullying (p<0.001).
Distribution of cases of victimization by bullying according to gender, age group, and occurrence of dental bullying.
Regarding OHRQoL, the OHIP-14 scores ranged from 0 to 20.84, with a median of 5.54. Regarding OHIP-14 categorization, 49.9% of adolescents reported an impact on OHRQoL, with the "psychological discomfort" (34.3%) and "social limitations" (25.6%) domains being the most affected, as shown in Table 4. OHIP-14 status was associated with sex (p<0.001), bullying victimization (p<0.001), and dental bullying (p<0.001) (Table 5).
Bivariate analysis between the impact on OHRQoL and the variables gender, age group, bullying victimization, and dental bullying.
Discussion
Bullying has been the target of multiple investigations in the field of dentistry. Even though with different methodological approaches, especially about the age group researched and the parameter adopted to estimate the bullying phenomenon, schoolchildren undoubtedly constitute the target population for surveys [12,14] and cohorts [11,15,22]. Specifically, in the context of oral health, the school environment is particularly important, given its relevance to the overall well-being and quality of life of children and adolescents [23,24].
In the Brazilian context, according to data from the Teaching and Learning International Survey, 28% of educational institutions that offer the final years of primary education identified regular acts of intimidation or bullying among students [25]. In the present study, which also included a sample composed of elementary school students, more than one-third of respondents (35.8%) were victims of bullying. In the first situation described, information was provided by principals of educational units, while in the last one, data were collected from the student population. Both methods for identifying bullying have strengths and weaknesses. Still, it is believed that self-reporting is particularly important, as in the school environment, many events remain restricted to students and are unknown to teachers and managers.
Regarding the prevalence of bullying victimization, the values reported in the international literature vary widely, with rates of 23.7% in Germany [26], 38.8% in Sub-Saharan Africa [2], 47% in Jordan [27], and 78.7% in Nigeria [28]. Globally, the prevalence rate of perpetration and victimization in the virtual environment also reaches variable levels according to the context [1]. Large differences in bullying prevalence are expected across populations due to cultural factors, public health policies, and different study methodologies [29,30]. In the national context, these data range from 6.2% [6] to 78% [31]. Such variations are related to the study design, the age of individuals, and the data collection instrument and typification of bullying episodes.
Bullying can occur directly through physical and/or verbal aggression and indirectly [32]. The verbal type ends up being the most reported among cases of victimization; therefore, being called names, humiliated, or insulted is usually reported [28,33,34] and was also the most prominent modality in this investigation. In the indirect subtype, the action of making or trying to make others dislike the student was recurrent. Regarding physical type, situations involving hair pulling and scratching were preponderant, unlike recent findings observed by other authors [3,8], in which actions such as hitting, kicking, pushing, or beating were identified as the most frequent.
Given the information described above, it is appropriate to consider the high occurrence of verbal bullying and the events involving the indirect modality. The first outcome can be justified by the ease of perpetration and lack of evidence [28]. The second, in turn, despite having reached a significant portion of schoolchildren, may be underestimated due to the difficulty of students and other social actors in recognizing it as a form of bullying [35]. The fact is that regardless of the type of perpetration, there are repercussions on the general health and quality of life of victimized individuals.
Physical appearance, which includes facial and dental characteristics, is considered one of the main reasons for bullying among students [36,37]. In this study, bullying victimization was associated with the occurrence of harassment for dental reasons, which was also described in a previous study [22]. Among victimized students, the prevalence of dental bullying was widely identified, with tooth positioning being the main reason mentioned. The result obtained (43.3%) is high when compared to values of 6.3%23 and 27%22 reported by other researchers. On the other hand, the occlusal characteristics identified as a triggering factor in bullying cases were also described by other authors [27,37,38]. Additionally, low levels of social competence and self-esteem are some of the implications related to victims of dental bullying, highlighting occlusal characteristics [39].
Being bullied due to visible oral characteristics, such as malocclusions or enamel defects, can negatively impact oral health-related quality of life, as the experience of ridicule and social stigmatization tends to amplify feelings of shame, low self-esteem, and anxiety in social contexts. This psychosocial process can lead to an increased perception of the need for treatment, avoidance of smiling and social interactions, and even a reduced need for dental care, which, together, compromise the functional, emotional, and social domains of OHRQoL [40,41].
The victimization profile identified in this research indicates that girls were the main targets of bullying, corroborating findings of other studies [29,30,42]. This evidence contrasts with other results, in which boys were predominantly the most affected victims [5,26,27]. A possible explanation for the majority occurrence of bullying episodes involving female students would be the reproduction in the school environment of the cultural logic that considers women inferior to men, being physically more fragile and more likely to suffer some type of violence [42]. Furthermore, OHRQoL was associated with sex, with a greater impact among women, as observed in other studies [14,42], whereas other studies did not show significant differences between sexes [37,38]. It was observed that different types of instruments and perceptions influence differently, in addition to the conception that females are more likely to be more concerned about their own health and aesthetic values.
The literature shows that younger adolescents have higher rates of bullying victimization than older ones [2,3,5,26,34]. This same trend was observed in this survey, with students aged 12-13 the most victimized, compared to those aged 14-15. In a way, this is understandable, since with increasing age and consequent physical and psychological development, episodes of bullying are better managed [32]. Furthermore, there is the possibility that “older” adolescents, when feeling uncomfortable with some aspect, develop an interest in seeking treatment to change the characteristics that cause them dissatisfaction or are used to perpetrate different types of bullying.
Dental aesthetics play a significant role in the quality of life for young people [43,44]. In the present study, OHRQoL was associated with victimization due to general and dental bullying, corroborating findings in the literature [14,37]. It is believed that OHRQoL can be impacted by different oral conditions [45], especially in adolescence [46,47], as at this stage, individuals who are dissatisfied with their body image and dental aspects are more likely to suffer bullying [48-50]. Being a victim of bullying consequently increases the risk of health problems, causing important changes in emotional well-being, social relationships, and performance of school activities [11]. Therefore, the results of this study showed a similar pattern, with psychological discomfort and social limitations being commonly affected domains.
In view of the above, even with some limitations, such as the study design and the inclusion of only municipal public schools, this study used a probabilistic sample and data collection instruments validated for the Brazilian population, which are relevant points for external validation of the findings. In this way, this study gathered essential information about the profile of bullying victimization, the prevalence of dental bullying and the impact on the OHRQoL of Brazilian adolescents living in an important city in northeastern Brazil. Future investigations should be developed to explore the details of the cause and effect relationships of the events presented here with a future perspective of ensuring the need to recognize and clinically manage aesthetic/occlusal characteristics, in addition to integrating anti-bullying actions in schools to mitigate the practice of bullying and protect the quality of life in relation to oral health in adolescence.
Conclusion
The prevalence of bullying victimization was high among elementary school students. Oral health-related quality of life was associated with bullying victimization, sex, and episodes of dental bullying. Psychological discomfort and social limitation domains were predominantly affected. Considering the repercussions of this phenomenon in the short and long term, it is relevant to develop public policies that include prevention and monitoring actions for victimized schoolchildren.
Financial Support
Data Availability
The data used to support the findings of this study can be made available upon request to the corresponding author.
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