What is peer victimisation and why is it important to understand?
Bullying is most common during early adolescence (age 11-14 years), when up to a third of all young people report experiences of physical, verbal, relational, or cyber victimisation by peers (e.g. being hit or kicked, called names, or excluded) (Modecki et al., 2014). In the formative years of adolescence, when the brain is still developing, young people can be particularly vulnerable to the negative effects of peer victimisation (e.g. Spear, 2009).
Previous research has found relationships between peer victimisation experiences and depression and anxiety (Reijntjes et al., 2010). Further, all three of these domains are related to a variety of negative wellbeing outcomes, such as poor school connectedness, social outcomes, quality of life, and physical health (e.g. Bogart et al., 2014; Hawker & Boulton, 2000; Juvonen, Wang, & Espinoza, 2011; Kokkinos & Kipritsi, 2012).
What was the aim of this research?
Untangling the direction and nature of the relationships between peer victimisation, depression and anxiety is difficult because they often co-occur. The study aimed to answer several questions:
- Does peer victimisation predict later depression, or anxiety, or both?
- Do depression or anxiety predict later peer victimisation?
- Do any of these domains have unique relationships with negative wellbeing outcomes, or is it their combined effect that predicts poorer functioning?
How was the study conducted?
The study used data from the nationally representative Longitudinal Study of Australian Children, specifically focusing on the cohort (group) of young people who started the study when they were aged 4 to 5 years (in 2004). The study analysed two waves of the data spanning the transition from childhood to early adolescence – when the children were aged 10 to 11 years, and two years later when they were aged 12 to 13 years.
The data consisted of questionnaires completed by children, their parents, and their teachers. Each reported on the child’s:
- depression and anxiety symptoms
- experiences of peer victimisation
- wellbeing outcomes, including school connectedness (i.e. school enjoyment and belonging), social outcomes (i.e. peer relationships), quality of life (i.e. self-belief and happiness) and global health (i.e. overall physical health).
What did the study find?
- Peer victimisation experiences at age 10-11 predicted higher levels of both depression and anxiety symptoms at age 12-13. The reverse was also true, as depression and anxiety symptoms at 10-11 years both independently predicted more severe peer victimisation experiences at 12-13 years.
- Peer victimisation, anxiety, and depression symptoms at age 10-11 each independently predicted worse levels of all of the wellbeing outcomes at age 12-13.
The above relationships did not differ for boys and girls.
What do these findings mean?
Depression, anxiety, and peer victimisation appeared to form a negative feedback loop in the transition from childhood to adolescence after accounting for their shared features, co-occurrence, and stability over time. Further, each domain had a unique role in predicting negative outcomes in early adolescence that spanned poorer school belonging, negative peer relationships, and lower self-efficacy, happiness, and global health.
In other words, it is not simply that internalising symptoms or peer victimisation are predicting these outcomes. Each domain adds to the negative effects of the others so that, for example, being anxious and being victimised is more detrimental than being anxious or being victimised. This is of considerable concern, given the prevalence and common co-occurrence of these experiences.
What are the implications for practice?
These findings have important implications for effective prevention, intervention, and treatment. Specifically, interventions for anxiety, depression or victimisation in isolation are unlikely to be effective for preventing subsequent negative outcomes. Further, if the bidirectional relationships found here reflect causal relationships, targeting only one of these domains (e.g. treating anxiety) is also likely to have poor long-term outcomes because the other untreated domains (e.g. depression and peer victimisation) will continue to reinforce it over time. Of course, causality cannot be determined here, given the use of observational data.
Overall, these results highlight the importance of implementing early and broad interventions that simultaneously target depression, anxiety and peer victimisation. For example, introducing programs in primary school that teach strategies for responding to peer victimisation as well as cognitive-behavioural skills to address symptoms of depression and anxiety may assist in preventing their onset and subsequent negative outcomes in adolescence.
Raising awareness of the common co-occurrence of peer victimisation, depression and anxiety (e.g. through education for parents, teachers, and practitioners working with children) would also assist in the early detection of emerging problems, and could provide opportunities for intervention and support before the patterns become more entrenched.
Limitations and future research
The strengths and limitations of the study should be kept in mind when interpreting these results.
The primary strength was the use of a large and nationally representative, multi-informant and prospective longitudinal study of children entering early adolescence.
The primary limitation was the restricted number of questions available for the assessment of the constructs of interest (i.e. anxiety, depression, peer victimisation). Future studies on this topic with more detailed measurement would be particularly valuable.
The small-to-moderate effect sizes found also highlighted that there are other influential factors accounting for changes in depressive symptoms and anxiety symptoms, and peer victimisation experiences over time. These factors should be explored in future studies with the aim of understanding the causal relationships among them and consequent implications for prevention and treatment.
