Cohort

{
  "id": "MLC-T-ENV-005527",
  "term": "Cohort",
  "field": "Environment",
  "definition": "1. A group of people within a population that can be aggregated because the variation in a characteristic of interest (e.g., exposure, age, education level) within the group is much less than the group-to-group variation across the population.\n\n2. A well-defined group of people who have had a common experience or exposure, who are then followed up for the incidence of new diseases or events, as in a cohort or prospective study. A group of people born during a particular period or year is called a birth cohort.\n\n3. A well-defined group of persons who have had a common experience or exposure and are then followed up, as in a cohort study or prospective study, to determine the incidence of new diseases or health events.\n\n4. A group of people within a population that can be aggregated because the variation in a characteristic of interest (e.g., exposure, age, education level) within the group is much less than the group-to-group variation across the population. [EPA 2004]\n\n5. A well-defined group of people who have had a common experience or exposure, who are then followed up for the incidence of new diseases or events, as in a cohort or prospective study. A group of people born during a particular period or year is called a birth cohort. [CDC 2005]\n\n6. Generally defined as a group of people within a population who are assumed to have identical exposures during a specified exposure period. The use of cohorts is a necessary simplifying assumption for modeling exposures of a large population. For the exposure assessment, the population is divided into a set of cohorts such that (1) each person is assigned to one and only one cohort, and (2) all the cohorts combined encompass the entire population.\n\n7. A group of people assumed to have identical exposures during a certain period.\n\n8. A fixed population in which membership is permanent (in contrast to a dynamic population). Also defined as a group of persons who experience a certain event in a specified period of time (e.g., a birth cohort of babies born in 1990 in New Zealand). [NZ 2002]",
  "subject": "Air",
  "references": [
    "EPA 2004",
    "CDC 2005",
    "CDC Glossary of Epidemiology Terms",
    "Thesaurus of Terms Used in Microbial Risk Assessment",
    "National Air Toxics Assessment (NATA) Glossary",
    "National Air Toxics Assessment (NATA) Glossary; AirToxScreen Glossary of Terms"
  ],
  "url": "https://mlchart.com/terminology/environment/cohort/"
}