The study of a population and those variables that bring about change in that population. Variables studied by demographers are age, sex, race, education, income, geographic trends, birth, and death, epidemiology; biometry.
The study of populations and environments or changes affecting populations.
The study of the populations of the world, their racial make-up, movements, birth rates, death rates, and other factors affecting the quality of life within them.
The study of populations and factors affecting their health.
The study of measurable characteristics of human populations. The characteristics may include population size, growth, density,, age, race, sex, or marital status. The information may be used to forecast health, needs and the use of health services.