https://medicine.yale.edu/ycci/clinicaltrials/

>The factors that allow someone to participate in a clinical trial are called “inclusion criteria,” and those that prevent someone from participating are called “exclusion criteria.”

>These criteria are based on factors such as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions.

>Many trials need healthy volunteers. Participants who are healthy are often needed to provide information that can be compared with people who have a particular disease.

>It is important to note that inclusion and exclusion criteria are not used to reject people personally. Instead, the criteria are used to identify appropriate participants and keep them safe. The criteria help ensure that researchers will be able to answer the questions they plan to study.