22. Urban and rural populations of the world: 1950–2030 Department of Economic and Social Affairs, Population Division. World urbanization prospects: the 2005 revision. New York: United Nations, 2006.
Scientific knowledge offers frameworks for understanding how variables at different levels combine within cities to influence health and disease. Technical knowledge includes the ability to measure, assess and intervene effectively within the urban environment. Organizational knowledge yields the ability to make institutional decisions that change practices and policies, and build coalitions for urban health. Political knowledge produces the capacity to mobilize resources to achieve health objectives.