An ELT Glossary : Cohort / Test Cohort

Definition : A cohort is a group of people who share the same characteristics. A test cohort is therefore composed of all the people who take a particular test at a particular time.  For example, anyone who takes IELTS in the summer of 2015 will be part of the IELTS test cohort for that exam session.

Further Information : The term cohort is also used in experimental research to describe the  group of people with specific common characteristics  (age, first language, second language proficiency level etc) involved in the experiment.