Background: While a legion of evidence indicates green spaces (e.g., parks) support health, there is a paucity of studies investigating their potential role in the development of prosocial behaviour (i.e., a range of behaviours that benefit others or promote positive relationships with others) across childhood and adolescence. The review of current evidence suggests that exposure to nearby green space may increase prosocial behaviour, but most of the evidence is cross-sectional, hindering causal inferences and understandings of temporality. Furthermore, most of this research has focused on the quantity of green space (i.e., the amount of green space available in the residential environment), neglecting the potentially critical importance of green space quality (i.e., aspects or attributes of green space that influence its utilisation) as a key determinant in its use and in the development of prosocial behaviour. Besides, candidate mediators and effect modifiers have not been comprehensively examined by previous studies, limiting understandings of plausible pathways and potential contingencies in who benefits. Therefore, research on green space quality and prosocial behaviour is important to improve the quality of current evidence and inform avenues on how to maximise the role of green space in shaping the development of prosocial behaviour. Enhancing the development of prosocial behaviour from a young age is important due to health, psychological, and social benefits.
Aims: This PhD thesis primarily aimed to examine the longitudinal association between green space quality and prosocial behaviour among children and adolescents. This thesis also investigated whether the accumulation of, or changes in, green space quality during childhood and adolescence were associated with the development of prosocial behaviour. Potential effect modifiers of the association and plausible pathways in which green space quality may influence prosocial behaviour were also assessed. In addition, the potential role of prosocial behaviour as a missing link – a candidate mediating variable – on the causal chain from green space quality to child health-related outcomes was tested.
Methods: This thesis used 10-year longitudinal data retrieved from the K-cohort of the Longitudinal Study of Australian Children. Data pertaining to green space quality, child prosocial behaviour, health-related outcomes (mental health, physical activity, and health-related quality of life (HRQOL)), and socioeconomic measures were biennially recorded from 4,983 children for a 10-year period, from 2004 (children aged 4-5 years: Wave 1) to 2014 (14-15 years: Wave 6). Green space quality was measured using caregiver reports on the availability of good parks, playgrounds, and play spaces in the neighbourhood. Caregivers also evaluated their child’s prosocial behaviour using the prosocial subscale from the Strengths and Difficulties Questionnaire (SDQ). Multilevel linear regression was applied to assess the association between green space quality and prosocial behaviour. Trajectories in green space quality experienced across childhood and adolescence were examined using latent class analysis. Causal mediation analysis was used to identify mechanistic pathways between green space quality and prosocial behaviour, as well as to test prosocial behaviour as a candidate mediator of the associations between green space quality and child health-related outcomes.
Results: The presence of quality neighbourhood green space was positively associated with child prosocial behaviour, irrespective of residential relocation. In addition, children whose caregiver perception of green space quality was ‘very good’ over time, trended from ‘good’ to ‘very good’ or from ‘very good’ to ‘good’ had higher prosocial behaviour than children of caregivers who consistently perceived nearby green space as low in quality. Evidence also indicated that the accumulation of very good quality green space over time may attenuate socioeconomic inequalities in prosocial behaviour. The association between green space quality and prosocial behaviour was found to be stronger among boys, children speaking only English at home, and children living in more affluent and/or remote areas. Moreover, physical activity enjoyment, social interaction, child and caregiver mental health, and HRQOL served as mechanistic pathways in which green space quality influenced prosocial behaviour. Prosocial behaviour was found as a mediator of the associations between green space quality and child health (mental health, HRQOL), and physical activity enjoyment.
Conclusions: The findings indicate that policies on provisioning and maintaining the quality of green space across childhood and adolescence in a targeted manner (e.g., prioritised in more disadvantaged and remote areas) can potentially buffer the negative impact of growing up in unfavourable socioeconomic circumstances and foster the development of prosocial behaviour. Improving the quality of neighbourhood green space that also encourages social interactions, physical activity enjoyment, and mental health might provide better support for the development of prosocial behaviour and vice versa. In addition, ensuring the neighbourhood to be safe and friendly for ethnic minorities is vital as it removes impediments to such populations gaining benefits from quality green space. Furthermore, identifying attributes of quality green space suitable for both boys and girls, and children from different age groups forms an important next step to maximise the benefits of quality green space for all.