Subjectively and objectively assessed social and physical environmental correlates of preschoolers' accelerometer-based physical activity.

Subjective traffic safety perceptions and participation in organized sports, an indicator and a result of parental support towards PA - i.e. subjective parental perceptions of environmental factors and family-level correlates which are more proximal to preschoolers - might be more central to PA in preschool age than objectively assessed community-level environmental features which tend to be more distal correlates. If replicable, targeting parental perceptions of environmental factors and parental support for PA in preschool age might be powerful leverages for public health policy.