Presenting Author: SALURBAL Investigators

ABSTRACT

Background: Defining what a “city” is an important challenge in urban and planetary health, especially in settings where data are sparser and lower quality.

Objectives: To apply a standard definition of a “city” across 10 Latin American countries to create a universe of “cities” greater than 100,000 population that would be composed of administrative units that are linkable to population, mortality, health, and other data in a multilevel database (i.e., city, administrative units like municipalities, neighborhood).

Methods: “Cities” with population greater than 100,000 were identified using the Atlas of Urban Expansion (AUE) and citypopulation.de (a website dedicated to compiling census data). The AUE defines a “city” geographically by the extent of its contiguous built-up area, regardless of administrative boundaries. Census data from citypopulation.de relies on local definitions of administrative units to identify cities. A list of cities combining both sources was shared with country partners for review. City-associated administrative units were identified by examining satellite imagery and geodatabases to determine which units encompassed any portion of a city’s observable built-up area. Subcomponents with >60% of population outside urban extents were flagged for potential exclusion from future analyses.

Results: There were 378 cities that met population criteria and 1,368 administrative units identified that encompassed the urban extent of these cities.

Implications: This practical approach may provide a guide for defining cities and their components that can be linked to other data for studies of urban health."

Authors: SALURBAL Investigators