[24] The well-established cognitive appraisal model of stress and coping developed by Lazarus[25] and the “sustained activation hypothesis”[26] can help to understand stress reactions to bullying. These models suggest that repeated bullying experiences in children’s life might cause a state of emotional distress that can lead to adverse health outcomes such as recurrent headache. To date, 2

meta-analyses[22, 23] have shown that bullied students can be affected by poor physical health and that these youths are about 2 times more likely than non-bullied agemates to report a variety of symptoms, such as headache, backache, abdominal pain, skin problems, vomiting, etc. However, both these meta-analytic reviews only reported an overall risk estimate this website for victims’ health problems and did not specifically focus MK-2206 supplier on headache. The current meta-analysis aims

at (1) estimating the risk for headache in children and adolescents who are bullied by peers (ie, victims) compared with non-bullied peers; (2) performing separate meta-analyses of longitudinal and cross-sectional studies; (3) testing for potential moderators of variation in the magnitude of effect sizes, that is, testing whether certain study features explain differences in the strength of the effect sizes. Several methods were used to identify relevant studies. First, electronic searches in PsychInfo, Pubmed, EMBASE, the Cochrane Library database, the Campbell Collaboration database, and Scopus were conducted in September 2013 with the following keywords: “bullying,” or “peer victimization” and “headache,” “somatic,” “psychosomatic,” and “physical health.” Second, the “cited by” function in Scopus was used to retrieve empirical articles that have cited the 2 meta-analyses[22, 23] on the association between bullying and health problems. Third, previous issues of the journal “Headache” were searched for relevant studies. Finally, review articles regarding consequences of bullying and the reference sections of the collected articles were reviewed

for possible relevant citations. If a study was not available in full-text, the corresponding author was contacted. This medchemexpress meta-analysis was planned, conducted, and reported in adherence to the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines.[27] A study had to meet the following a priori criteria to be included. The most basic requirement was the inclusion of measures of bullying victimization at school in childhood or adolescence and of headache. Consistent with the international literature, bullying was defined as a deliberate, repeated exposure to aggressive acts performed by a peer or a group of peers with higher power or strength than the bullied schoolmate (ie, the “victim”).[17, 18] These measures could include (1) self-report questionnaires; (2) peer or adult reports; or (3) an interview that resulted in a quantitative rating of peer victimization and headache frequency.