Multilevel Thinking and Life Course Perspectives Inform Public Health Practice: A Public Health of Consequence, November 2018

Perhaps an obvious example is that it is now lingua franca in public health to recognize that alcohol outlet policies at the group level influence population-level alcohol use and its consequences.5 A life course perspective suggests that an individual's present health was shaped and produced by the individual's health over the life course and that health is even transmitted intergenerationally.6 This framing suggests that when we focus on health at any particular point in time, our understanding of what affects health is limited. Conversely of course, this perspective urges us to consider the health consequences of present actions, to recognize that decisions made today-for instance, regarding forces that influence global environmental climate change-will have health implications in coming decades.7 These two perspectives are, when properly understood, transformative to our work, and they substantially influence how we should conduct our scholarship and choose to act to improve public health. Using data on more than 180 000 US children in 2793 census tracts over seven years, this study shows that crowding is associated with decreases in child cognitive development and communication skills and that in highpoverty subsamples, commute time is associated with decreases in social competence and emotional maturity.