We wish to propound a model for the determination or prediction of life-span of human beings with respect to their habitat (rural or urban), in developing nations.
You may also consider how these factors affect the model above:
-Food
-Healthcare
-Education
-Sanitation
-Income level, etc.
You may need to code your population: rural and urban. Then use common statistical tests to verify their difference according to place of residency or changing trend with respect to time. For trend test see link below: