“…Such a metric could then be monitored as natural experiments occur (e.g., New York City’s Community Parks Initiative ( New York City Department of Parks & Recreation, 2019 , Huang et al, 2016 ) or as individuals relocate within or between cities, thereby providing critical longitudinal evidence and advancing the field towards the latter phases of the behavioral epidemiology framework ( Koohsari et al, 2015 , Sallis et al, 2000 ). Similarly, environmental justice has been a major emphasis of park researchers, with the exposures examined ranging from open space acreage to specific features to diverse quality metrics ( Kamel et al, 2014 , Lotfi and Koohsari, 2011 , Crawford et al, 2008 , Mavoa et al, 2015 , Macintyre et al, 2008 , Hashem, 2015 , Hoffimann et al, 2017 , Shen et al, 2017 ). Employing a common metric of park access that accounts for both availability and attributes would increase comparability over time and across locations in monitoring improvements in the equitable distribution of green space.…”