Urbanization and mortality decline

We investigate the relationship between mortality decline and urbanization, which has hitherto been proposed by demographers but has yet to be tested rigorously in a global context. Using cross-national panel data we find evidence of a robust negative correlation between crude death rates and urbanization. The use of instrumental variables suggest that this relationship is causal, while historical data from the early 20th century suggests that this relationship holds in earlier periods as well. Finally, we find robust evidence that mortality decline is correlated with urbanization through the creation of new cities rather than promoting urban growth in already-extant cities.