Use of natural environments is associated with reduced inequalities in child mental wellbeing: A cross-sectional analysis using global positioning system (GPS) data.

ABSTRACT

Exposure to natural environments may benefit child mental wellbeing whilst offering a lever to reduce health inequalities. However, understanding of these relationships is limited by evidence from indirect measures of exposure. We objectively measured children's direct use of natural environments-and use in low or high physical activity (PA) states-and associated this with their mental wellbeing. We then examined moderation by sex and household income. Using global positioning system and accelerometry data from children (n = 640), we measured mean daily time in natural environments ('total use'), which we stratified by PA level as 'passive use' (sedentary and light PA) and 'active use' (moderate and vigorous PA). Logistic regression associated exposures with dichotomised Strengths and Difficulties Questionnaire outcomes (internalising difficulties; externalising difficulties; prosocial behaviour), with interactions to examine moderation. A 10-minute increase in total use was associated with 10.5 % lower risk of abnormal internalising outcomes (OR 0.895; 95 % CI 0.809, 0.990), and 13.2 % lower risk of abnormal externalising outcomes (OR 0.868; 95 % CI 0.776, 0.990). This suggests that âˆ¼ 60 min of daily total use was associated with 50 % lower risk of abnormal internalising and externalising outcomes. The relative effects of passive and active use were equal, but their associations were moderated by income independently for specific outcomes. For externalising outcomes, the risk of abnormal scores in lower-income children reduced as passive use increased (P = 0.027) but remained constant for higher-income children. For prosocial outcomes, the likelihood of normal scores increased with active use in lower-income children, but not higher-income children (P = 0.005). Sex did not moderate these associations. The findings suggest that targeted interventions supporting disadvantaged children to use natural environments could help address inequalities in mental wellbeing. Further, the moderated associations with types of use suggest the equigenic effects of natural environments may operate through multiple pathways.