Impact of Green Space Exposure on Children's and Adolescents' Mental Health: A Systematic Review.

In recent years, the interest in the relationship between exposure to green spaces and children's and adolescents' mental health has risen. This systematic review aims to provide an overview of observational studies assessing the association between empirical green space exposure with standardized outcome measures of mental health problems, mental well-being and developmental problems in children, adolescents and young adults. The PRISMA statement guidelines for reporting systematic reviews were followed. A PubMed and Scopus search resulted in the inclusion of 21 studies. The evidence consistently suggests a beneficial association between green space exposure and children's emotional and behavioral difficulties, particularly with hyperactivity and inattention problems. Limited evidence suggests a beneficial association with mental well-being in children and depressive symptoms in adolescents and young adults. These beneficial associations are resistant to adjustment for demographic and socio-economic confounders, which thus may represent independent links. Mediating factors and the variability of this association between different age groups are discussed. From a precautionary principle, evidence up to now demands the attention of policy makers, urban planners and mental healthcare workers in order to protect children's and adolescents' mental health in light of rapid global urbanization by providing sufficient exposure to green spaces.