Adolescent Development Research Articles

Children’s and Adolescents’ Use of Nature During the COVID-19 Pandemic in a Very Green Country

Play, physical activity, and social interaction with other children in nature are important for healthy and social development in childhood and adolescence. The extent to which lockdown policies during the COVID-19 pandemic impacted the way children engaged in outdoor activities remains unclear, especially in a country with free access to abundant nature during the pandemic. We performed a national survey of parents (n = 1002) in Norway in January 2021 to uncover changes in outdoor play for children (6–12 years, n = 396) and adolescents (13–19 years, n = 606) compared with the situation before the lockdown on 12 March 2020. Ten months after the start of the COVID-19 lockdown, 38% of the parents reported that their children played and spent time outside ‘less than usual’ in their neighborhood, compared with 15% who reported ‘more than usual’ time spent outside. Parents indicated that the children’s play activities were highly organized and institutionalized, and when the activities ceased, their children had less motivation to spend time outdoors and tended to engage more in screen-based activities indoors. We conclude that while children and adolescents had many opportunities to be outdoors in natural settings during the COVID-19 pandemic restrictions, they did so much less than before the lockdown.

Gene-environment interactions in the influence of maternal education on adolescent neurodevelopment using ABCD study.

Maternal education was strongly correlated with adolescent brain morphology, cognitive performances, and mental health. However, the molecular basis for the effects of maternal education on the structural neurodevelopment remains unknown. Here, we conducted gene-environment-wide interaction study using the Adolescent Brain Cognitive Development cohort. Seven genomic loci with significant gene-environment interactions (G×E) on regional gray matter volumes were identified, with enriched biological functions related to metabolic process, inflammatory process, and synaptic plasticity. Additionally, genetic overlapping results with behavioral and disease-related phenotypes indicated shared biological mechanism between maternal education modified neurodevelopment and related behavioral traits. Finally, by decomposing the multidimensional components of maternal education, we found that socioeconomic status, rather than family environment, played a more important role in modifying the genetic effects on neurodevelopment. In summary, our study provided analytical evidence for G×E effects regarding adolescent neurodevelopment and explored potential biological mechanisms as well as social mechanisms through which maternal education could modify the genetic effects on regional brain development.

Theory of Mind Development in Middle Childhood and Adolescence: Accuracy and Preference for Mental-State Reasoning

ABSTRACT While there is a steady increase in research examining growth of theory of mind (ToM) over middle childhood and adolescence, there remains a paucity of studies on how older children employ ToM to interpret the behaviors of others. We conducted two studies and used a new task – the Mr Bean task – based on a wordless video to examine understanding of a variety of mental states and a preference for mental state reasoning in children and adults. Study 1 examined 131 children (5–13 years) and 418 adults in New Zealand and included open-ended questions requiring participants to explain agents’ behaviors. Study 2 also used a Mr Bean video and tested 80 children (6–16 years) and 49 young adults in New Zealand but asked multiple-choice questions, each with a correct mental state option, a correct general reasoning option, and an incorrect version of each option. Our study provided the following novel findings. First, children’s ToM continued to progressively improve from middle childhood to adolescence, and through to adulthood in that, relative to adults, children erred more frequently when they reasoned using mental states. Second, explanations referring to emotions, intentions and cognitions were used more frequently with age. Third, children were less likely to use mental state reasoning and more likely to use general reasoning compared to adults; only adults preferred to use mental state rather than general reasoning. Fourth, the advantage in adult ToM was related to their superior vocabulary but not fluid intelligence. Our findings provide clear evidence that not just ToM accuracy, but also preference for mental state reasoning continue to evolve from middle childhood through to adulthood.

Running, walking, and cross-country skiing: how to shape adolescents’ personalities through physical activity?

Adolescence is crucial for personality development, and sports play a significant role. This study investigates the impact of various sports on the personality traits of junior high and high school students in Shandong Province, focusing on neuroticism, extraversion, openness, agreeableness, and conscientiousness. Utilizing data from the “Database of Youth Health,” we employed Seemingly Unrelated Regression (SUR) and Generalized Structural Equation Modeling (GSEM) to analyze the effects of physical activity on personality development. Findings reveal that walking significantly enhances openness and decreased neuroticism, while jogging/running substantially improves extraversion, agreeableness, and conscientiousness. Cross-country skiing, however, negatively impacts all assessed personality traits. In addition, the importance of gender differences in the relationship between physical activity and personality development was revealed. The results offer insights for promoting adolescent personality development through targeted sports activities.

Narrative Communication of Teachers’ Support Needs for Violence-Based Trauma in the Schools

Community violence is a serious public health problem, and research on community violence consistently documents a relationship between exposure to community violence and adolescents’ psychological and behavioral challenges, which, when considered cumulatively, can be understood as collective trauma. Preventing and mediating exposure to community violence by local schools is, thus, an important part of efforts to promote healthy adolescent development. As a societal problem, community violence and its socio-psychological effects lend themselves to an interdisciplinary approach for researching the problem and possible intervention and mitigation in local schools. The integrative, interdisciplinary approach to problem analysis in this study provides a framework for addressing trauma due to community violence as it affects the school environment. Narrative analysis, as a method of discovery, reveals the struggles of high school teachers dealing with the effects of violence-based trauma on their students. Policy recommendations and implications for future research are included.

Relationship between maltreatment and mental health in adolescents: A school-based study in Indonesia.

Maltreatment affects emotional development in adolescents and inhibits social adjustment. This study aimed to analyze the relationship between maltreatment and mental health among adolescents. A cross-sectional study was conducted on adolescents in the first and second grades of middle school (12-14 years old) and high school (15-17 years old) in eight cities and municipalities in the province, selected through several stages of simple random sampling (N = 1837). The International Society for the Prevention of Child Abuse and Neglect (ISPCAN) Child Abuse Screening Tool for Children (ICAST-C) questionnaire for detecting maltreatment was translated, simplified, and validated by an expert based on a theoretical framework that involved pediatricians, public health, and medicolegal perspectives. The Strengths and Difficulties Questionnaire (SDQ) was used to assess emotional states. ICAST-C and SDQ scores were transformed to logit values using Rasch model analysis. Distribution frequency and linear regression were used for data analysis. The results indicated that 85.6% of adolescents aged 12-14 and 83% of those aged 15-17 experienced physical maltreatment, while 89.4% of the 12-14 age group and 82.9% of the 15-17 age group experienced psychological maltreatment. The emotional states of the two groups were 52.8% and 59.2%, respectively. There was a significant correlation between the experience of physical maltreatment and emotions among 12-14 (r1 = 0.148 (0.190-0.257)) and 15-17 years old (r1 = 0.047 (0.084-0.156)). There was a significant correlation between the experience of psychological maltreatment and emotions among 12-14 years old '(r2 = 0.191 (0.270-0.350)) and 15 to 17 years old (r2 = 0.097 (0.167-0.252)). In conclusion, physical and psychological maltreatment were correlated with mental health states among adolescent students in West Java, Indonesia.

Effects of football training on cognitive performance in children and adolescents: a meta-analytic review

BackgroundThe cognitive development of children and adolescents is crucial for their academic success and overall well-being. Physical activity has been linked to improved cognitive performance, but the specific effects of football training on cognitive function in this population remain unclear. This meta-analytic review aimed to comprehensively evaluate the impact of football training on cognitive performance in children and adolescents.MethodsLiterature was searched through PubMed, PsycINFO, SPORTDiscus, Embase, and Web of Science. Eligible studies were randomized controlled trials (RCTs) or crossover designs assessing cognitive performance following football training interventions. Outcome measures included attention, inhibitory control, and working memory. Data synthesis and meta-analysis were performed to determine the overall effect sizes.ResultsTwelve studies were included in the meta-analysis, comprising 1,574 children and 94 adolescents. Football training demonstrated moderate, statistically significant effects on attention (Hedges’ g = −0.77, p = 0.01), inhibitory control (Hedges’ g = −0.67, p = 0.02), and working memory (Hedges’ g = −0.44, p = 0.03). The findings suggest that football training positively influences cognitive performance in children and adolescents.ConclusionFootball training holds promise for enhancing cognitive function in children and adolescents, particularly in attention, inhibitory control, and working memory. Theoretical frameworks emphasizing environmental enrichment, cardiovascular fitness, and cognitive component skills help elucidate the underlying mechanisms. Future research should explore how football training compares to other sports and assess whether integrative drills that combine cognitive elements with skill practice offer greater cognitive benefits than skill training alone. These insights support the inclusion of football in educational programs to foster cognitive development.

Sequential Dual Mediating Effects of Smartphone Dependence and Aggression on the Relationship Between Negative Parenting Attitudes and Depressive Symptoms Among Adolescents

ABSTRACTThis study examined the sequential dual mediating effects of negative parenting attitudes, smartphone dependence and aggression on depressive symptoms among adolescents. Data were obtained from the 2018 Korean Children and Youth Panel Survey (KCYPS) conducted by the National Youth Policy Institute. Using a multistage stratified cluster sampling method, the 2018 KCYPS comprehensively examined various aspects of the growth and development of children and adolescents. The study sample included a nationally representative sample of 2541 adolescents. PROCESS macro Model 6 was used to examine the sequential dual mediating model that not only examines the effects of negative parenting attitudes on smartphone dependence and aggression but also establishes the sequential causal relationship between smartphone dependence and aggression, ultimately confirming the direct and indirect effects on depressive symptoms of adolescents. The significance of the mediation effect was verified by applying the bootstrapping method. The findings demonstrated that negative parenting attitudes increased smartphone dependence, which, in turn, elevated depressive symptoms among adolescents. Furthermore, negative parenting attitudes increased smartphone dependence, which heightened aggression, ultimately contributing to depressive symptoms among adolescents. Based on these findings, this study has practical and policy implications for preventing depressive symptoms among adolescents. Prioritizing efforts to reduce smartphone dependence and aggression among adolescents while promoting positive parenting attitudes can play a crucial role in addressing this issue.

Abstract 4119595: Impact of Environmental Noise and Sleep Health on Pediatric Hypertension Incidence: The ABCD Study

Background: Pediatric hypertension is linked to environmental factors like neighborhood noise disrupting sleep, which is crucial for health. The specific interaction between noise and sleep health in causing hypertension still needs to be explored. Research Question: How does the interaction between neighborhood environmental noise and sleep health affect the incidence of pediatric hypertension? Aims: To estimate the incidence of hypertension in American adolescents and to investigate the individual and joint effects of exposure to neighborhood environmental noise and sleep health on its incidence. Methods: Our analysis involved 3,320 individuals from the Adolescent Brain Cognitive Development (ABCD) study across 21 US cities, followed prospectively from 2018-2020 (T0) to 2020-2022 (T1). We included only those with complete data: Fitbit-tracked sleep, blood pressure, height, neighborhood noise, and relevant covariates (biological sex, ethnicity, pubertal stage, waist circumference). Hypertension was defined as average blood pressure at or above the 95th percentile for age, sex, and height, based on American Academy of Pediatrics guidelines. Sleep health was classified based on daily duration into three categories: healthy (9-12 hours), moderately healthy (1 hour below or above optimal), and low (more than 1-hour deviation). Neighborhood noise exposure was quantified using median anthropogenic noise levels at night, linked to participants’ zip codes. We estimated hypertension incidence and its relative risks (RR, 95% CI), examining the effect (individual and joint) of sleep health and environmental noise on hypertension risk. Results: At Time 1 (T1), the mean age was 13.9 years; 47.6% were girls, and 52.9% were White. Hypertension prevalence in 2018-2020 was 1.7% (CI95% 1.4; 2.1), and the incidence after two years was 2.9% (CI95% 2.4; 3.6). Night noise was 58.4 decibels, 29.9% healthy sleep time (T0); 20.3% healthy sleep time (T1). Adolescents with more favorable healthy sleep showed a lower risk of developing hypertension RR= 0.63 (CI 95% 0.25 to 0.82). We found no association between noisy neighborhoods and no joint effects (neighborhood noise + sleep health) with hypertension incidence. Conclusions: Adequate sleep is associated with a lower risk of hypertension in adolescents. However, no significant link was found between neighborhood noise and pediatric hypertension. This highlights the need for public health efforts to improve sleep quality in youth.

Traditional Value Identity and Mental Health Correlation Among Chinese Adolescents

This study explores the identity of traditional values among Chinese adolescents and its correlation with their mental health. A questionnaire survey, utilizing the Confucian Traditional Values Scale and the Secondary School Students’ Mental Health Scale, was conducted with 500 students from Grade 7 through the final year of college. Our results showed the following: (1) adolescents generally agree with traditional values; (2) there were no significant differences in overall agreement with traditional values among adolescents based on their gender, place of birth, class cadre status, only-child status, or academic major, though differences were observed in specific dimensions based on these variables; (3) traditional values identity varied across grade levels, with senior high school students showing notably higher identification than junior high school and college students, peaking in the second year of senior high school; and (4) there is a significant negative correlation between adolescents’ traditional values identity scores and their mental health scores, indicating that higher traditional values identity scores are associated with better mental health levels. These findings highlight the positive influence of traditional values on the development and well-being of Chinese adolescents, underscoring the importance of integrating these values into educational and developmental frameworks in China and other East Asian regions with similar cultural backgrounds.

Impact of Environmental Noise and Sleep Health on Pediatric Hypertension Incidence: ABCD Study.

Pediatric hypertension is linked to environmental factors like neighborhood noise disrupting sleep, which is crucial for health. The specific interaction between noise and sleep health in causing hypertension still needs to be explored. We analyzed data from 3320 participants of the ABCD (Adolescent Brain Cognitive Development) study, recruited across 21 US cities and monitored from 2018 to 2020 through 2020 to 2022. Participants with complete data on Fitbit-tracked sleep, blood pressure, height, neighborhood noise, and covariates (biological sex, race and ethnicity, pubertal stage, waist circumference) were included. Hypertension was defined as average blood pressure ≥95th percentile for age, sex, and height. Sleep health was categorized on the basis of daily duration: healthy (9-12 hours), moderately healthy (±1 hour from optimal), and low (≥1 hour deviation). Noise exposure was measured as median nighttime anthropogenic noise levels by zip code. The incidence of hypertension increased from 1.7% (95% CI, 1.4-2.1) in 2018 to 2020 to 2.9% (95% CI, 2.4-3.6) in 2020 to 2022. Adolescents with healthier sleep had a lower risk of developing hypertension (relative risk, 0.63 [95% CI, 0.25-0.82]), while no significant effects were found for neighborhood noise alone or in combination with sleep health. Adequate sleep significantly reduces the risk of hypertension in adolescents, independent of environmental noise exposure. These findings underscore the importance of promoting good sleep hygiene among youth to mitigate hypertension risk.

Asthma and Memory Function in Children.

Asthma is a chronic respiratory disease affecting approximately 5 million children in the US. Rodent models of asthma indicate memory deficits, but little is known about whether asthma alters children's memory development. To assess whether childhood asthma is associated with lower memory abilities in children. This cohort study used observational data from the Adolescent Brain Cognitive Development (ABCD) Study, a multisite longitudinal investigation that began enrollment in 2015. Approximately 11 800 children aged 9 to 10 years were enrolled at baseline with follow-up at 1 and 2 years. Participants were selected based on exposures described subsequently to determine longitudinal and cross-sectional associations between asthma and memory. Data were analyzed from Month year to Month year. Asthma was determined from parent reports. For the longitudinal analysis, children were selected if they had asthma at baseline and at the 2-year follow-up (earlier childhood onset), at the 2-year follow-up only (later childhood onset), or no history of asthma. For the cross-sectional analysis, children were selected if they had asthma at any time point, or no history of asthma. The comparison group of children with asthma history was matched on demographic and health covariates for each analysis. The primary outcome was episodic memory. Secondary outcomes included processing speed, inhibition and attention. Four hundred seventy-four children were included in the longitudinal analysis (earlier childhood onset: 135 children; mean [SD] age, 9.90 [0.63] years; 76 [56%] male; 53 [28%] Black, 29 [21%] Hispanic or Latino, and 91 [48%] White; later childhood onset: 102 children; mean [SD] age 9.88 [0.59] years; 54 [53%] female; 22 [17%] Black, 19 [19%] Hispanic or Latino, and 83 [63%] White; comparison: 237 children; mean [SD] age, 9.89 [0.59] years; 121 [51%] male; 47 [15%] Black, 48 [20%] Hispanic or Latino, and 194 [62%] White). Children with earlier onset of asthma exhibited lower rates of longitudinal memory improvements relative to the comparison group (β = -0.17; 95% CI, -0.28 to -0.05; P = .01). Two thousand sixty-two children were selected for the cross-sectional analysis (with asthma: 1031 children; mean [SD] age, 11.99 [0.66] years; 588 [57%] male; 360 [27%] Black, 186 [18%] Hispanic or Latino, and 719 [54%] White; without asthma: 1031 children; mean [SD] age 12.00 [0.66] years; 477 [54%] female; 273 [21%] Black, 242 [23%] Hispanic or Latino, and 782 [59%] White). Children with asthma (1031 children) showed lower scores on episodic memory (β = -0.09; 95% CI, -0.18 to -0.01; P = .04), processing speed (β = -0.13; 95% CI, -0.22 to -0.03; P = .01), and inhibition and attention (β = -0.11; 95% CI, -0.21 to -0.02; P = .02). In this cohort study, asthma was associated with memory difficulties in children, which may be more severe if asthma onset is earlier in childhood and may extend to executive function abilities.

The Importance of Sports Activities in the Formation of Skills for an Active and Healthy Lifestyle in Young People

Sports activities play a crucial role in developing the skills for an active and healthy lifestyle in adolescents, providing students with the opportunity to experience and engage in a variety of activities in order to develop their motor, social, and intellectual skills. The purpose of the paper is to highlight the essential role that sports activities have in skills training, necessary for an active and healthy lifestyle in adolescents. The objectives of the research include examining the physical benefits of sports activities on the health of adolescents, highlighting the development of motor skills through sports activities, and analyzing the impact of sports activities on the social and emotional development of adolescents, especially through identifying strategies and resources available to encourage adolescents to participate in sports activities and adopt an active and healthy lifestyle. Sports activities are essential for training the skills for an active and healthy lifestyle in adolescents, contributing to the improvement of physical and mental health, the development of social and emotional skills, and the increase of self-confidence and self-esteem.

Level of Physical and Psychomotor Skills in Children Practising Climbing in their Extracurricular Activities

Our study examines physical and psychomotor development in 12-13-year-olds engaged in climbing extracurricular activities. 24 children from Brașov and Bacău were evaluated in 2023, by using Pearson correlation coefficients to analyse relationships between indicators. Strong linear correlations were revealed at the somatic development level, at the mental ability level as well as at the level of the motor capacity testing back, abdominal and limb strength. These outcomes can give insights into the integrated development of adolescents engaged in climbing activities.

Study identifies eight traumatic and ACEs to psychiatric risk across development

There are eight TRACEs (traumatic and adverse childhood experiences) which can lead to mental health and cognitive problems during adolescents, according to researchers. Using the Adolescent Brain Cognitive Development (ABCD) data from the National Institutes of Health, the researchers drew on reports from youth and their caregivers to look at longitudinal change and how it is moderated by the TRACEs.

The Impact of Parental Depressive, Anxiety, and Stress Symptoms on Adolescents’ Mental Health and Quality of Life: The Moderating Role of Parental Rejection

Background/Objectives: Parental internalizing issues, particularly maternal mental health, can significantly influence adolescents’ mental health by altering parenting behaviors and roles. This study explores the role of parental rejection in moderating the relationship between parental depressive, anxiety, and stress symptoms and adolescents’ mental health and quality of life. Methods: One hundred thirty eight mothers (mean age: 47.96, SD = 5.06 years) and 68 fathers (mean age: 51.07, SD = 5.53 years) of adolescents aged 12–18 completed measures on mental health, parental rejection, and adolescent well-being. Results: Maternal rejection was found to moderate the relationship between maternal anxiety symptoms and adolescents’ quality of life, as well as between maternal anxiety symptoms and adolescents’ mental health problems. Paternal rejection moderated the relationship between paternal stress symptoms and adolescents’ mental health. However, parental rejection did not moderate the relationship between parental depression and adolescents’ quality of life or mental health. Conclusions: These findings highlight the distinct roles of maternal and paternal rejection in adolescent development and suggest that parental mental health, particularly anxiety and stress, has a significant impact on adolescent well-being. Future studies should consider the influence of both parents and focus on longitudinal effects. These results emphasize the need for interventions addressing parental rejection to improve adolescent outcomes.

Associations Between Gender Diversity and Eating Disorder Symptoms in Early Adolescence.

To assess associations between multiple dimensions of gender diversity with eating disorder symptoms in a national cohort of U.S. early adolescents. This cross-sectional study utilized data from the Adolescent Brain Cognitive Development (ABCD) Study (N = 10,092, Mage = 12.9 years, 2019-2021). Gender diversity was measured using multiple dimensions, including categorical gender identity (e.g., transgender, cisgender), categorical and continuousfelt gender (congruence between gender identity and assigned sex), ordinal gender non-contentedness (dissatisfaction with one's gender), and ordinal gender expression (communication of gender through appearance and mannerisms). Multivariable logistic regression models were used to analyze the associations among gender diversity measures and eating disorder symptoms, adjusting for potential confounders. Greater felt gender diversity was associated with self-worth tied to weight (OR 1.30, 95% CI 1.11-1.53), binge eating (OR 1.24, 95% CI 1.06-1.46), and distress with binge eating (OR 1.32, 95% CI 1.09-1.59). Greater gender expression diversity was associated with self-worth tied to weight (OR 1.16, 95% CI 1.02-1.33), distress with binge eating (OR 1.26, 95% CI 1.04-1.51), and characteristics of binge eating episodes (OR 1.33, 95% CI 1.06-1.66). Gender non-contentedness was associated with self-worth tied to weight (OR 1.38, 95% CI 1.20-1.58) and compensatory behaviors related to weight gain (OR 1.12, 95% CI 1.01-1.26). Transgender identity was not significantly associated with any eating disorder symptoms. We found that greater gender diversity across multiple dimensions was associated with various eating disorder symptoms, and that measures beyond binary gender identity may be important to assess gender diversity in early adolescence.

Development of Self-Reported Reward Responsiveness and Inhibitory Control and the Role of Clinical and Neural Predictors.

Understanding the development of adolescent reward responsiveness and inhibitory control is important as they are implicated in key outcomes, such as depression. However, relatively few studies have examined the self-reported experience of this development longitudinally, and past findings have been mixed. Here, we examined the longitudinal development of self-reported reward responsiveness and inhibitory control in youth, as well as clinical and neural measures as predictors of these longitudinal trajectories. We assessed 223 youth aged 9-17 across 36 months. We modeled growth trajectories of several measures of reward responsiveness and inhibitory control using multilevel models. We tested reward-related functional connectivity, depression symptoms, and parental risk for psychopathology as moderators of longitudinal growth. Self-reported inhibitory control increased linearly across adolescence. However, contrary to hypotheses and common models of adolescent development, self-reported reward responsiveness decreased linearly across adolescence. Baseline functional connectivity and clinical risk measures did not significantly moderate trajectories. Results suggest that within-person changes in the phenomenological experience of reward responsiveness may not match developmental expectations based on cross-sectional and neuroimaging studies. More attention is needed to the longitudinal study of subjective experience of reward responsiveness.

Study links adolescent cannabis use with psychosis

A cohort study of 11,868 adolescents found that those who used cannabis at any point reported a greater number of psychosis symptoms, and more distress from those symptoms, compared to teens who never used cannabis. This study, “Psychosis Spectrum Symptoms Before and After Adolescent Cannabis Use Initiation,” published last week in JAMA Psychiatry, sought to answer the question of whether the cannabis use is an effort to self‐medicate underlying psychosis, or contributes to increased vulnerability to psychosis. Findings were consistent with the self‐medication hypothesis. The researchers concluded that it is important to account for both shared vulnerability, and self‐medication effects, when modeling cannabis‐psychosis risk associations. The study used data from 5 waves across 4 years of followup from the Adolescent Brain Cognitive Development (ABCD) Study.

Influence of campus exclusion on bullying behavior of junior high school students: role of callous-unemotional traits and family caring

School bullying significantly impacts adolescent physical and mental development. The current study aimed to explore the effect of campus exclusion on school bullying behavior among junior high school students and the role of callous-unemotional traits and family caring. The Campus Exclusion Questionnaire, Olweus Child Bullying Questionnaire, Callous-Unemotional Trait Scale, and Family Caring Scale were completed by 705 students. A moderated mediation model was analyzed using SPSS 24.0. Results indicated that both campus exclusion and callous-unemotional traits positively predicted bullying behavior. Callous-unemotional traits partially mediated the relationship between campus exclusion and bullying behavior. Additionally, family caring moderated the link between callous-unemotional traits and bullying behavior, mitigating adverse effects. The study highlighted family caring’s protective role against bullying linked to adverse school experiences. Therefore, collaboration between schools and families is crucial to reduce bullying.