What Works for Whom in School-Based Anti-bullying Interventions? An Individual Participant Data Meta-analysis.

The prevalence of bullying worldwide is high (UNESCO, 2018). Over the past decades, many anti-bullying interventions have been developed to remediate this problem. However, we lack insight into for whom these interventions work and what individual intervention components drive the total intervention effects. We conducted a large-scale individual participant data (IPD) meta-analysis using data from 39,793 children and adolescents aged five to 20 years (Mage = 12.58, SD = 2.34) who had participated in quasi-experimental or randomized controlled trials of school-based anti-bullying interventions (i.e., 10 studies testing nine interventions). Multilevel logistic regression analyses showed that anti-bullying interventions significantly reduced self-reported victimization (d = - 0.14) and bullying perpetration (d = - 0.07). Anti-bullying interventions more strongly reduced bullying perpetration in younger participants (i.e., under age 12) and victimization for youth who were more heavily victimized before the intervention. We did not find evidence to show that the inclusion of specific intervention components was related to higher overall intervention effects, except for an iatrogenic effect of non-punitive disciplinary methods-which was strongest for girls. Exploratory analyses suggested that school assemblies and playground supervision may have harmful effects for some, increasing bullying perpetration in youth who already bullied frequently at baseline. In conclusion, school-based anti-bullying interventions are generally effective and work especially well for younger children and youth who are most heavily victimized. Further tailoring of interventions may be necessary to more effectively meet the needs and strengths of specific subgroups of children and adolescents.

Does affirming children's autonomy and prosocial intentions help? A microtrial into intervention component effects to improve psychosocial behavior.

Prior research has related children's prosocial behavior to overall well-being, and stimulating prosocial behavior is the aim of many social-emotional skills interventions. This study assessed if affirming children's autonomy stimulates their psychosocial behavior. We conducted a three-arm microtrial with four repeated measures to assess if a social-emotional skills intervention with an autonomy affirmation component had an additive effect on children's behavior as compared to a "regular" intervention focused exclusively on teaching social-emotional skills and a no-treatment control condition. Our sample consisted of 779 children in Grades 4-6 (Mage = 10.61, SD = 0.93). Findings from latent change modeling demonstrated that the social-emotional skills intervention with an autonomy affirmation component yielded superior effects as compared to the "regular" intervention and the no-treatment control condition on the improvement of internalizing and externalizing problem behavior in the three-month period after the intervention. The intervention with autonomy affirmation did not yield superior effects on prosociality and social skills, self-efficacy, and self-esteem or self-perceived competence. The absence of these effects may be attributed to the dosage of the interventions implemented-the affirmation of children's autonomy may require more than four sessions to sort observable effects. Overall, however, the findings of this study provide an initial suggestion that it may be beneficial to affirm children's autonomy and prosocial intentions when enhancing children's behavior.

Effects of Implementing Multiple Components in a School-Wide Antibullying Program: A Randomized Controlled Trial in Elementary Schools.

This study investigates the effectiveness of the PRIMA antibullying program for elementary education using a cluster-randomized trial with two experimental conditions (with and without student lessons) and a control group. Students of 31 schools participated in the study (N = 3,135; Mage  = 10 years). Multilevel regression analyses demonstrated positive effects of the program on peer-reported victimization and reinforcing behavior. Implementing multiple program components was related to stronger program effects. The results provide partial experimental evidence for the beneficial effects of combining student lessons and teacher training in antibullying programs. Future experimental research is needed to investigate other approaches that reduce not only peer-reported victimization, but also self-perceived bullying and victimization.

Effective Components of Social Skills Training Programs for Children and Adolescents in Nonclinical Samples: A Multilevel Meta-analysis.

Social skills training (SST) programs for nonclinical children and adolescents are known to have positive effects on social skills, but it remains unclear how distinct training components are related to program effects. This multilevel meta-analysis examines how psychoeducation (i.e., exercises aimed at the transfer of knowledge), psychophysical components (i.e., physical exercises aimed at improving self-confidence and trust in others), skill-building components (i.e., exercises aimed at improving interpersonal skills), and cognitive-emotional components (i.e., exercises aimed at changing emotions and cognitions) are independently related to SST program effects. We extracted data from 97 articles describing 839 effect sizes. Training content data were extracted from 60 corresponding SST programs. Our results showed that SST programs had a positive effect on the development of interpersonal skills and emotional skills in nonclinical samples: d = .369, 95% CI [.292, .447], p < .001. This effect was positively influenced by the inclusion of psychoeducation and skill-building components. The inclusion of psychophysical components and the number of cognitive-emotional components did not influence program effects. For psychoeducation and skill-building components, we observed a curvilinear relationship between intensity and effect size: programs including three to six psychoeducational exercises yielded larger effect sizes compared to programs with more or fewer psychoeducational exercises, and programs with 11 to 20 skill-building exercises outperformed programs with more or fewer skill-building exercises. These findings are an indication that psychoeducational components and skill-building components are related to larger SST program effects, granted that the dosage is right.

A Social Gradient in the Effects of the Skills for Life Program on Self-Efficacy and Mental Wellbeing of Adolescent Students.

BACKGROUND: The goal of the current study was to evaluate the effects of the Social Emotional Learning program Skills 4 Life on mental health and its risk factors self-esteem, self-efficacy, and social interaction skills in students of secondary schools. METHODS: A cluster randomized controlled study was conducted, including 38 schools (66 classes; grades 7 to 9) for secondary education, with a 1 year and 20 months follow-up (teachers and students reports). RESULTS: The intervention was effective in improving self-efficacy, depressive symptoms, and teacher-reported psychological problem behavior, all after 20 months. Stratified analyses showed effects in mainly lower educational level students. CONCLUSION: The Skills 4 Life curriculum is effective in improving the mental health and self-efficacy among adolescents, especially for adolescents from lower educational level, a group that is most prone to ill mental health.

Missed cases in the detection of child abuse based on parental characteristics in the emergency department (the Hague Protocol).

INTRODUCTION: We aimed to assess the number of "missed cases" in the detection of child abuse based on the Hague Protocol. This protocol considers 3 parental characteristics of ED adult patients to identify child abuse: (1) domestic violence, (2) intoxication, and (3) suicide attempt or auto-mutilation. METHODS: This study focuses on parents whose children should have been referred to the Reporting Centre for Child Abuse and Neglect (RCCAN) in the Hague, the Netherlands, according to the guidelines of the Hague Protocol. Data were collected from all referrals by the Medical Centre Haaglanden (Medisch Centrum Haaglanden) to the RCCAN in the Hague between July 1 and December 31, 2011. The hospital's database was searched to determine whether the parents had visited the emergency department in the 12 months before their child's referral to the RCCAN. RESULTS: Eight missed cases out of 120 cases were found. The reasons for not referring were as follows: forgetting to ask about children and assuming that it was not necessary to refer children if parents indicated that they were already receiving some form of family support. DISCUSSION: Barriers to identifying missing cases could be relatively easy to overcome. Regular training of emergency nurses and an automated alert in the electronic health record to prompt clinicians and emergency nurses may help prevent cases being missed in the future.

Detecting child abuse based on parental characteristics: does the Hague Protocol cause parents to avoid the emergency department?

OBJECTIVES: The Hague Protocol is used by professionals at the adult Emergency Departments (ED) in The Netherlands to detect child abuse based on three parental characteristics: (1) domestic violence, (2) substance abuse or (3) suicide attempt or self-harm. After detection, a referral is made to the Reporting Center for Child Abuse and Neglect (RCCAN). This study investigates whether implementing this Protocol will lead parents to avoid medical care. METHOD: We compared the number of patients (for whom the Protocol applied) who attended the ED prior to implementation with those attending after implementation. We conducted telephone interviews (n = 14) with parents whose children were referred to the RCCAN to investigate their experience with the procedure. RESULTS: We found no decline in the number of patients, included in the Protocol, visiting the ED during the 4 year implementation period (2008-2011). Most parents (n = 10 of the 14 interviewed) were positive and stated that they would, if necessary, re-attend the ED with the same complaints in the future. CONCLUSION: ED nurses and doctors referring children based on parental characteristics do not have to fear losing these families as patients.

What parental characteristics can predict child maltreatment at the Emergency Department? Considering expansion of the Hague Protocol.

The Hague Protocol considers three parental characteristics of Emergency Department adult patients to identify child abuse: (a) domestic violence, (b) intoxication, and (c) suicide attempt or auto mutilation. This study investigated whether additional parental characteristics could be included to improve the chance of detection. Using a nested case-control design, we compared parents identified as child abusers who were missed by the Protocol with a matched group of nonabusing parents. The parental characteristics used were, among others, all physical injuries possibly resulting from domestic violence, psychological, or mental complaints that might indicate elevated domestic stress levels and the number of Emergency Department visits during the previous year. None of the characteristics were statistically significantly associated with child abuse. The Hague Protocol will not be improved by adding one or more of the characteristics that were investigated.

[Young people with Down syndrome: independence and social functioning]. / Zelfredzaamheid van jongeren met Down-syndroom.

OBJECTIVE: To determine the level of independence and social functioning in young people with Down syndrome. DESIGN: Cross-sectional study. METHOD: Via the Dutch Down Syndrome Foundation (Stichting Downsyndroom), we asked parents of children with Down syndrome born in 1992, 1993 or 1994 to complete a written questionnaire about their child. This questionnaire contained the following standardised lists: the 'Dutch social competence rating scale for people with a learning disability', the 'Child behaviour checklist' and the 'Children's social behaviour questionnaire', and additional questions on background characteristics. The results of this Dutch cohort were compared with available data on peers without Down syndrome. RESULTS: Data from 322 young people with Down syndrome, mean age 18.4 years (range 16.8-19.9 years), were collected (response 63%). Almost 60% of participants mastered basic skills of independent functioning, such as maintaining adequate standards of personal hygiene, preparing breakfast and being able to spend at least 30 minutes at home alone. About 10% of the participants had basic skills such as cooking and paying in a shop. Nine out of ten participants had more problems with social functioning than peers without Down syndrome, mainly with social interaction, processing information and regulating their emotions. Half of the participants had clinically relevant behavioural problems. CONCLUSION: The results of this study show that young people with Down syndrome have limited practical and social skills, and more behavioural problems than their peers without Down syndrome. In daily life they are to a greater or lesser extent dependent on others, and need lifelong support.

Facilitators and barriers to the successful implementation of a protocol to detect child abuse based on parental characteristics.

To determine the critical facilitating and impeding factors underlying successful implementation of a method to detect child abuse based on parental rather than child characteristics known as the Hague Protocol. The original implementation region of the protocol (The Hague) was compared to a new implementation region (Friesland), using analysis of referrals, focus group interviews (n=6) at the Emergency departments (ED) and at the Reporting Centers for Child abuse and Neglect (RCCAN) as well as questionnaires (n=76) at the EDs. Implementation of the Hague Protocol substantially increased the number of referrals to the RCCAN in both regions. In Friesland, the new implementation region, the number of referrals increased from 2 out of 92,464 patients (three per 100,000) to 108 out of 167,037 patients (62 per 100,000). However in Friesland, child abuse was confirmed in a substantially lower percentage of cases relative to the initial implementation region (62% vs. 91%, respectively). Follow-up analyses suggest that this lower positive predictive value may be due to the lack of training for RCCAN professionals concerning the Hague Protocol. The focus group interviews and questionnaires point to time limitations as the main impediment for implementation, whereas an implementation coach has been mentioned as the most important facilitating factor for success. The Hague Protocol can be used to detect child abuse beyond the initial implementation region. However, training is essential in order to assure a consistent evaluation by the RCCAN.

Mainstream and special school attendance among a Dutch cohort of children with Down Syndrome.

OBJECT: To determine the level of mainstream education in a nationwide cohort of adolescents with Down Syndrome (DS), and to find characteristics related to mainstream or special school attendance. METHOD: Dutch children with DS born in 1992, 1993 or 1994, were assessed when 16-19 years old. Parents scored school enrolment between the age of 4-18 years, general characteristics and the levels of intellectual disability using the Dutch Social Competence Rating Scale. Associations between disability and years in mainstream school were assessed by ordinal logistic regression, adjusting for sex and parental education. RESULTS: We collected data from 170 boys and 152 girls (response 63%); mean age 18.3 years (ranges 16.8-19.9). Intellectual disability was mostly moderate (43%). Most children (74%) entered mainstream education between 4 and 6 years of age. At 13 years 17% was in mainstream school and 7% stayed in up to 16 years. From the age of 8 years onwards the majority was in special education, while 6% never attended school. Girls were more often in mainstream school and stayed in longer. Level of disability was significantly associated with number of years in mainstream education. CONCLUSION: Three out of four Dutch children with DS entered mainstream primary education, however late entry and high dropout are common.

Practical and social skills of 16-19-year-olds with Down syndrome: independence still far away.

Survival of children with Down syndrome (DS) has improved considerably, but insight into their level of daily functioning upon entering adulthood is lacking. We collected cross-sectional data from a Dutch nationwide cohort of 322 DS adolescents aged 16-19 (response 62.8%) to assess the degree to which they master various practical and social skills, using the Dutch Social competence rating scale and the Children's Social Behavior Questionnaire. Up to 60% mastered some of the skills required for independent functioning, such as maintaining adequate standards of personal hygiene and preparing breakfast. Less than 10% had achieved basic skills such as basic cooking and paying in a shop. It is difficult for DS people to master all the skills necessary to live independently. Ninety percent of adolescents with DS experience significant problems in social functioning.

Problem behavior of individuals with Down syndrome in a nationwide cohort assessed in late adolescence.

OBJECTIVE: To assess problem behavior in adolescents with Down syndrome and examine the association with sex and severity of intellectual disability. STUDY DESIGN: Cross-sectional data of a Dutch nationwide cohort of Down syndrome children aged 16-19 years were collected using a written parental questionnaire. Problem behavior was measured using the Child Behavior Checklist and compared with normative data. The degree of intellectual disability was determined using the Dutch Social competence rating scale. RESULTS: The response rate was 62.8% (322/513), and the mean age 18.3 years (SD ± 0.8). The total score for problem behavior was higher in adolescents with Down syndrome than in adolescents without Down syndrome (26.8 vs 16.5; P < .001). Overall, 51% of adolescents with Down syndrome had problem scores in the clinical or borderline range on 1 or more Child Behavior Checklist subscales; this is more than twice as high as adolescents without Down syndrome. Adolescents with Down syndrome had more internalizing problems than their counterparts without Down syndrome (14% and 9%, respectively, in the clinical range); the percentages for externalizing problems were almost equal (7% and 9%, respectively, in the clinical range). The highest problem scores in adolescents with Down syndrome were observed on the social problems and thought problems subscales (large to very large standardized differences). Male sex and/or more severe mental disabilities were associated with more behavioral problems. CONCLUSIONS: Serious problem behavior is more prevalent in adolescents with Down syndrome. This demonstrates the need for a focus on general behavior improvement and on the detection and treatment of specific psychopathology in individuals with Down syndrome.

A new protocol for screening adults presenting with their own medical problems at the Emergency Department to identify children at high risk for maltreatment.

Identifying child abuse and neglect solely on the grounds of child characteristics leaves many children undetected. We developed a new approach (Hague protocol) based on characteristics of parents who attend the Emergency Department (ED) because they have the following problems: (1) intimate partner violence, (2) substance abuse, or (3) suicide attempt or other serious psychiatric problems. The goal of this protocol is to enable the Reporting Center for Child Abuse and Neglect (RCCAN) to rapidly assess family problems and offer voluntary community based support to these parents. The aim of this study is to assess whether this protocol for screening adults presenting for care in the Emergency Department can identify children at high risk for maltreatment. A before and after study was conducted at 9 EDs in 3 regions in the Netherlands (one intervention region and 2 control regions). During the period January 2006 to November 2007, prior to the introduction of the Hague protocol, from a total of 385,626 patients attending the ED in the intervention region 4 parents (1 per 100,000) were referred to the RCCAN. In the period after introduction of the protocol (December 2007 to December 2011), the number rose to 565 parents from a total of 885,301 patients attending the ED (64 per 100,000). In the control region, where the protocol was not implemented, these figures were 2 per 163,628 (1 per 100,000) and 10 per 371,616 (3 per 100,000) respectively (OR=28.0 (95 CI 4.6-170.7)). At assessment, child abuse was confirmed in 91% of referred cases. The protocol has a high positive predictive value of 91% and can substantially increase the detection rate of child abuse in an ED setting. Parental characteristics are strong predictors of child abuse. Implementing guidelines to detect child abuse based on parental characteristics of parents attending the adult section of the ED can increase the detection rate of child abuse and neglect allowing appropriate aid to be initiated for these families.

[Reasons for having oneself vaccinated against HPV: implications for the future provision of information]. / Redenen om zich te laten vaccineren tegen HPV: implicaties voor toekomstige informatievoorziening.

OBJECTIVE: To examine which factors determined the participation in HPV vaccination programme in 2009 and 2010. DESIGN: Retrospective cross-sectional study. METHOD: Random samples of Dutch girls who had been invited for the HPV vaccination programme in 2009 and 2010, as well as their mothers, were drawn from an Internet panel. Data were gathered by means of a web-based questionnaire. RESULTS: The questionnaire was filled out by 243 girls and 511 mothers from cohort 2009, and by 225 girls and 250 mothers from cohort 2010. In both cohorts, the following factors were related to HPV vaccination: perceived susceptibility for cervical cancer, general opinion about the vaccine, anticipated feelings of regret about the decision made, specific beliefs (e.g. about the protective effects of the vaccine), trust in responsible authorities, perceived opinion of others about the vaccination and their HPV vaccination participation, the degree to which vaccination is taken for granted and the extent to which the decision to have oneself vaccinated is unambiguously perceived. In both cohorts, these factors explained a large and significant part of the variation in HPV vaccination; namely, 89% and 81% of the girls and 94% and 82% of the mothers from the cohorts in 2009 and 2010, respectively. CONCLUSION: This study provides insight into the reasons behind the disappointing participation in the HPV vaccination programme. In order to increase HPV vaccination uptake, future communication should provide balanced information about facts and opinions, and advantages and disadvantages of the vaccination. There should also be room for uncertainty in the choice whether or not to have oneself vaccinated.

Determinants of HPV vaccination intentions among Dutch girls and their mothers: a cross-sectional study.

BACKGROUND: The Dutch government recently added universal Human Papilloma Virus (HPV) vaccination for 12-year-old girls to the existing national immunization program. The participation rate for the initial catch-up campaign for girls aged 13 to 16 years in 2009 was lower (47%) than expected (70%). To inform future HPV information campaigns, this paper examines the social and psychological determinants of the HPV vaccination intentions of girls aged 13 to 16 years and their mothers who were targeted by the Dutch catch-up campaign of 2009. METHODS: A random sample of girls and their mothers was chosen from the Dutch vaccination register and received a letter inviting them to participate (n = 5,998 mothers and daughters). In addition, a random sample was recruited via an online panel by a marketing research company (n = 650 mothers; n = 350 daughters). Both groups were asked to complete a web-based questionnaire with questions on social demographic characteristics, social-psychological factors and HPV vaccination intention. Backward linear regression analyses were conducted to examine which social-psychological factors were most dominantly associated with vaccination intention. RESULTS: Data from 952 mothers (14%) and 642 daughters (10%) were available for the intended analyses. The contribution of social demographic variables to the explained variance of HPV vaccination intention was small but significant for mothers (ΔR² = .01; p = .007), but not significant for daughters (ΔR² = .02; p = .17) after controlling for HPV vaccination uptake and the sample. In addition, social-psychological determinants largely contributed to the explained variance of HPV vaccination intention of mothers (ΔR² = .35; p < .001) and daughters (ΔR² = .34; p < .001). Attitudes, beliefs, subjective norms and habit strength were significantly associated with participants' HPV vaccination intentions. CONCLUSIONS: Because of the large contribution of social-psychological variables to the explained variance of HPV vaccination intentions among the mothers and daughters, future communication strategies targeting HPV vaccination uptake should address attitudes, beliefs, subjective norms and habit strength. There is a need for longitudinal research to confirm the causality of the association between these determinants and HPV vaccination behavior indicated by this study.

Development, problem behavior, and quality of life in a population based sample of eight-year-old children with Down syndrome.

OBJECTIVE: Children with Down syndrome (DS) have delayed psychomotor development. We investigated levels of development, problem behavior, and Health-Related Quality of Life (HRQoL) in a population sample of Dutch eight-year-old children with DS. Developmental outcomes were compared with normative data of eight-year-old children from the general population. METHOD: Over a three-year-period all parents with an eight-year-old child with DS were approached by the national parent organization. Developmental skills were assessed by means of the McCarthy Scales of Children's Ability. To measure emotional and behavioral problems we used the Child Behavior Checklist. HRQoL was assessed with the TNO-AZL Children's Quality of Life questionnaire. Analyses of variance were applied to compare groups. RESULTS: A total of 337 children participated. Mean developmental age was substantially lower than mean calendar age (3.9 years, SD 0.87 and 8.1 years, SD 0.15 respectively). Mean developmental age was significantly lower among boys than girls (3.6 (SD 0.85) and 4.2 years (SD 0.82) respectively; p<0.001). Compared with the general population, children with DS had more emotional and behavioral problems (p<0.001). However on the anxious/depressed scale, they scored significantly more favorably (p<0.001). Significantly lower HRQoL scores for the scales gross motor skills, autonomy, social functioning and cognitive functioning were found (p-values<0.001). Hardly any differences were observed for the scales physical complaints, positive and negative emotions. CONCLUSION: Eight-year-old children with DS have an average developmental delay of four years, more often have emotional and behavioral problems, and have a less favorable HRQoL compared with children from the general population.

Reliability and validity of the Spanish version of the TAPQOL: a health-related quality of life (HRQOL) instrument for 1- to 5-year-old children.

OBJECTIVES: To evaluate the reliability, and construct validity of the Spanish version of the TNO-AZL preschool children quality of life (TAPQOL). METHODS: A consecutive sample of children (3 months to 5 years old) was recruited from primary care centers and two teaching hospitals in Spain. The TAPQOL and a set of questions related to their child's health status were administered to parents. Clinical diagnoses were collected from clinical records. Principal component analysis (PCA) with varimax rotation was used to analyze the instrument's structure. Effect size (ES) and analysis of variance (ANOVA) were used to analyze differences between subgroups known to be in poor health compared to the healthy subgroup. RESULTS: A total of 228 children participated in the study (response rate=95%). Ten of the 12 scales showed more than 30% ceiling effect. All dimensions except one had Cronbach's alpha coefficients greater than 0.7. PCA explained 75% of the variance. Healthy children in general had better scores than the other subgroups. Children at risk of poor health outcomes and those with respiratory problems scored lower in several scales than the healthy subgroup. CONCLUSIONS: Although the Spanish TAPQOL shows a non-negligible ceiling effect, it seems to be a reliable and valid instrument for Spanish infants and toddlers, and with similar psychometric characteristics to the original version. Future studies should try to improve questionnaire's structure and assess its sensitivity to change.

Effects of antibullying school program on bullying and health complaints.

OBJECTIVE: To evaluate the effects of an antibullying school intervention in elementary schools. DESIGN: Two-year follow-up randomized intervention group-control group. SETTING: Forty-seven elementary schools in the Netherlands. PARTICIPANTS: Three thousand eight hundred sixteen children aged 9 to 12 years. INTERVENTION: During the first study year, an antibullying school program was implemented in the schools in the intervention group. MAIN OUTCOME MEASURES: A questionnaire measuring bullying behavior, depression, psychosomatic complaints, delinquent behavior, and satisfaction with school life and peer relationships was filled out by the students at 3 times to obtain the following data: a baseline measurement, a first-effect measurement at the end of the first year, and a second-effect measurement at the end of the second year. RESULTS: The number of bullied children decreased by 25% in the intervention group compared with the control group (relative risk, 0.75; 95% confidence interval, 0.57-0.98). The intervention group also showed a decline in the scale scores of victimization (-1.06 vs 0.28; P< .01) and active bullying behaviors (-0.47 vs 0.12, P< .05). Self-reported peer relationships also improved in the intervention schools (0.48 vs 0.11; P< .05), and there was a trend for a decrease in reported depression in the intervention schools (-0.33 vs -0.10; P< .10). At follow-up, there were no differences between the intervention and control groups for the outcome measures. Schools had also lowered their antibullying activities during the second study year. CONCLUSIONS: An antibullying school policy can reduce bullying behavior. To keep bullying at a consistently low level, schools must continue antibullying measures every year. Continued counseling may help schools in their efforts to establish a lasting antibullying policy.

Do bullied children get ill, or do ill children get bullied? A prospective cohort study on the relationship between bullying and health-related symptoms.

OBJECTIVES: A number of studies have shown that victimization from bullying behavior is associated with substantial adverse effects on physical and psychological health, but it is unclear which comes first, the victimization or the health-related symptoms. In our present study, we investigated whether victimization precedes psychosomatic and psychosocial symptoms or whether these symptoms precede victimization. DESIGN: Six-month cohort study with baseline measurements taken in the fall of 1999 and follow-up measurements in the spring of 2000. SETTING: Eighteen elementary schools in the Netherlands. PARTICIPANTS: The study included 1118 children aged 9 to 11 years, who participated by filling out a questionnaire on both occasions of data collection. OUTCOME MEASURES: A self-administered questionnaire measured victimization from bullying, as well as a wide variety of psychosocial and psychosomatic symptoms, including depression, anxiety, bedwetting, headaches, sleeping problems, abdominal pain, poor appetite, and feelings of tension or tiredness. RESULTS: Victims of bullying had significantly higher chances of developing new psychosomatic and psychosocial problems compared with children who were not bullied. In contrast, some psychosocial, but not physical, health symptoms preceded bullying victimization. Children with depressive symptoms had a significantly higher chance of being newly victimized, as did children with anxiety. CONCLUSIONS: Many psychosomatic and psychosocial health problems follow an episode of bullying victimization. These findings stress the importance for doctors and health practitioners to establish whether bullying plays a contributing role in the etiology of such symptoms. Furthermore, our results indicate that children with depressive symptoms and anxiety are at increased risk of being victimized. Because victimization could have an adverse effect on children's attempts to cope with depression or anxiety, it is important to consider teaching these children skills that could make them less vulnerable to bullying behavior.