Quality or quantity? Exploring the relationship between Public Open Space attributes and mental health in Perth, Western Australia.

Mental health is a public health priority globally. Public Open Space (POS) may enhance mental health by facilitating contact with nature and the development of supportive relationships. Despite growing interest in the influence of the built environment on mental health, associations between POS attributes and mental health remain relatively unexplored. In particular, few studies have examined the relative effects of the quantity and quality of POS within a neighbourhood on mental health. Guided by a social-ecological framework, this study investigated the relationship between POS attributes (i.e., quantity and quality) and better mental health (i.e., low risk of psychological distress) in residents of new housing developments in the Perth metropolitan area, Western Australia. The extent to which relationships between POS attributes and mental health were confounded by psychosocial factors (e.g., social support, sense of community) and frequent use of POS was also explored. Data were obtained from a cross-sectional survey (n = 911), a POS audit, and Geographical Information Systems, and was analysed using logistic regression. Approximately 80% of survey participants were at low risk of psychological distress. Residents of neighbourhoods with high quality POS had higher odds of low psychosocial distress than residents of neighbourhoods with low quality POS. This appeared to be irrespective of whether or not they used POS. However, the quantity of neighbourhood POS was not associated with low psychological distress. From a mental health perspective, POS quality within a neighbourhood appears to be more important than POS quantity. This finding has policy implications and warrants further investigation.