Who Can Participate?

Clinical studies have standards outlining who can participate. These standards are called eligibility criteria and are listed in the protocol. Some research studies seek participants who have the illnesses or conditions that will be studied, while other studies are looking for healthy participants.


The factors that allow someone to participate in a clinical study are called inclusion criteria, and the factors that disqualify someone from participating are called exclusion criteria. They are based on characteristics such as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions.

It is important to note that inclusion and exclusion criteria are not used to reject people personally. Rather, the criteria are specific to each study and are used to find appropriate participants. The criteria help ensure that researcher will be able to answer the question which they plan to study while keeping the participants safe.