Which geographical factors do you consider to be the most important in explaining why low income and middle income countries are just that?

Not all people in a country have the same risk of mortality or life expectancy at a given age. It has long been recognized that people of higher social status typically have better health, lower mortality rates, and higher life expectancy (see, for example, Lynch et al., 2004). Social inequality differs from the factors discussed in the preceding chapters of this volume in that it has been described as a “fundamental” cause of differences in exposure to, and experience of, risk for poor health outcomes.

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