In addition, every study site will have a PI. The PI may give you medical examinations during the study, and he or she will be responsible for dealing with any serious medical problems that come up as a result of your study participation. Remember the PI may not know which arm of the study you are in.

Every study site also has an Institutional Review Board (IRB). The IRB is responsible for protecting the rights of participants in a trial. It must approve every trial that is conducted at that institution, and it must review the trial every few months. The IRB can stop a trial if the trial doesn’t do what it promised or if it exposes people to harm. You can complain to the IRB if you have a problem while in a study.

Finally, there is the study’s Data and Safety Monitoring Board (DSMB), made up of experts who review the information (data) from the trial at different time points and who can delay or stop the study if there are safety concerns.

When you sign the informed consent, you should be given contact information for the study coordinator or study nurse, the principal investigator and the chairman of the IRB. That way, if any problems come up during the study, you can easily contact the right person.

As you can see, despite the unknown risks of being in a clinical trial, there are many safety checks and built-in mechanisms to protect you as a study participant.