Local case-control sampling
Local case-control sampling is a way of studying a group of people to try and understand what might be causing a certain health problem or disease. Instead of studying everyone in the world, researchers can look at a smaller group of people who live close together.
For example, imagine that researchers want to learn more about why people develop cancer. Instead of studying everyone in the world who has cancer, they can find a group of people who live close to each other, like in the same town or city. This group of people could include some people with cancer and some people without cancer. The people with cancer are called cases and the people without cancer are called controls. The researcher would ask all the cases and controls lots of questions about the things they do, like the food they eat and their daily activities. By comparing the answers of the cases and controls, the researcher might be able to figure out what causes people to get cancer.
For example, imagine that researchers want to learn more about why people develop cancer. Instead of studying everyone in the world who has cancer, they can find a group of people who live close to each other, like in the same town or city. This group of people could include some people with cancer and some people without cancer. The people with cancer are called cases and the people without cancer are called controls. The researcher would ask all the cases and controls lots of questions about the things they do, like the food they eat and their daily activities. By comparing the answers of the cases and controls, the researcher might be able to figure out what causes people to get cancer.