Abstract and Introduction
Abstract
Background and objectives.—Being bullied at school is a risk factor for a variety of negative consequences, including somatic problems. The purpose of this meta-analysis is to determine the association between peer victimization and headache in the school-age population.
Methods.—A systematic literature search was conducted in September 2013 to identify observational studies that examined the association between being bullied and headache in children and adolescents. Odds ratios (OR) were pooled by using a random-effects model. Moderator and sensitivity analyses were conducted.
Results.—Twenty studies, including a total of 173,775 participants, satisfied the pre-stated inclusion criteria. Fourteen studies reported data on the prevalence of headache, which was on average 32.7% (range: 9.1–71.7%) in the bullied group and 19.1% (range: 5.3–46.1%) in the control group. Two separate meta-analyses of the association between being bullied and headache were performed on 3 longitudinal studies (OR = 2.10, 95% confidence interval = 1.19–3.71) and 17 cross-sectional studies (OR = 2.00, 95% confidence interval = 1.70–2.35), respectively. Results showed that bullied children and adolescents have a significantly higher risk for headache compared with non-bullied peers. In the cross-sectional studies, the magnitude of effect size significantly decreased with the increase of the proportion of female participants in the study sample. No further moderators were statistically significant.
Conclusions.—The positive association between bullying victimization and headache was confirmed. Further research on the environmental factors that may influence this symptom is needed.
Introduction
Recurrent headache is the most frequent neurological symptom during school age and one of the most frequent manifestations of pain in childhood and adolescence. A recent systematic review showed that headache is very common across the world with about 60% of children and adolescents reporting this symptom over at least a 3-month period. Moreover, epidemiological studies pointed out that the prevalence of headache has increased over the last decades in the school-age population. Quite recently, studies on the potential risk factors for youth's headache have drawn attention to the role of psychological and social factors, including negative experiences at school. For example, stressors in the school environment, such as schoolwork pressure, negative feelings about school, perception of being treated badly or unfairly by teachers, fear of failure, and harassment by peers turned out to be associated with higher levels of headache in children and adolescents.
A serious and frequent source of concern in children's and adolescents' school life is bullying, that is, a repetitive physical or psychological abuse by a stronger schoolmate or group on a weaker peer. Epidemiological studies across countries indicate that 10–20% of students are frequently bullied by schoolmates. Importantly, pediatric and psychological research is increasingly demonstrating the adverse consequences of being bullied at school for children's and adolescents' psychosocial adjustment, health, and medicine use. The well-established cognitive appraisal model of stress and coping developed by Lazarus and the "sustained activation hypothesis" 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 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 for victims' health problems and did not specifically focus 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.