Criteria used to determine who is eligible (or ineligible) for recruitment into a clinical study.

Inclusion criteria are based on the condition(s) and populations that a study is focusing on, such as specific infections or age groups for antibiotic trials.

Exclusion criteria are used to exclude potential participants, for example if they have additional conditions that could complicate interpretation of results, if use of an intervention might place them at risk, or if medications they are taking could interfere with the trial intervention.