The relationship between bullying behaviours in childhood and physician-diagnosed internalizing disorders

Bullying and its potential consequence for poor mental health constitutes a public health concern, yet there is a dearth of longitudinal studies examining the topic. This study examines the temporal relationship between childhood bullying behaviours (being a victim, being a bully, or being a bully and a victim) and physician-diagnosed internalizing disorders over a 7-year timespan.

Data from the 2003 Children's Lifestyle and School performance Study (CLASS), a population-based health survey of grade 5 students in Nova Scotia, Canada were linked to administrative health-care records to examine the relationship between bullying behaviours and services where a physician diagnosis of an internalizing disorder (ID) was received. Negative binomial regression analyses were conducted to examine this relationship.

Of the 4694 participants, 33.3% reported being involved in some form of bullying behaviour and 24.1% had a service where a physician diagnosis of ID was given over a 7-year timespan. Compared with children who reported not being involved in bullying behaviours, children who reported being a victim of bullying had a higher rate of subsequent physician-diagnosed ID services (IRR = 1.38, 95% CI = 1.11, 1.70). Children who reported being a bully had a lower rate of ID services (IRR = 0.67, 95% CI = 0.46, 0.99), while there was no difference for those who reported between being a bully and a victim (bully-victim) with respect to ID services.

Bullying behaviours should be considered a serious public health issue due to their high prevalence in school environments and detrimental effects on the mental health of adolescents.