Clinical Trials

Helping Others by Contributing to Medical Research

All about clinical trials


An arm is a group of people in a clinical trial who receive the same intervention or medication. A trial may have two or more arms to compare research outcomes. For example, one arm may receive an investigational medication or vaccine and the other arm may receive a placebo or the standard of care.

Disease Disparity

When specific patient populations (i.e. age, ethnic, racial, regional, sex) have certain diseases and conditions at higher rates than others, this is known as a disease or health disparity. Disease disparities within these patients may be caused by differences in genetic or environmental factors.


When you enroll in a clinical trial, that means the trial doctor and staff determined that you are eligible, and you have agreed to participate.

Informed Consent Form (ICF)

The ICF is a document that will be provided to you prior to joining a trial. It helps explain the trial details in easy-to-understand language to fully inform you about trial participation. You must read and sign the ICF before you can enroll in the trial.

Investigational Medication or Vaccine

The investigational medication or vaccine is what is being evaluated in the trial. Typically, it is not approved for public use for the condition being studied and may only available in clinical trials.


Phases are the series of trials (i.e. phase I, II, etc.) an investigational medication or vaccine will go through to determine if there is scientific evidence that an investigational medicine may prevent or treat a disease or condition. Each phase generates data to assess if an investigational medication or vaccine may be approved by the FDA (or Regulatory agencies) for public use.

Plain Language Summary

A Plain Language Summary (PLS) is a summary of the key results of a trial provided after a trial is complete. Each PLS is written in a way that’s easy to read, and helps participants understand more about the research they have contributed to.


When you are randomly assigned to one of the different arms or groups in the clinical trial, this is known as randomization. This typically occurs when you are enrolled in a trial comparing an investigational medication or vaccine to the standard of care or placebo.

Role of Placebo

A placebo is an inactive substance that looks like the investigational drug or treatment being studied in some clinical trials used in some clinical trials. It is used in the control group or arm of a trial to compare with the investigational medicine/vaccine being studied.

Regulatory Authorities

Each country has a set of regulatory authorities that reviews the results of clinical trials. Based on the information gathered about an investigational medication in clinical trials, these authorities will determine whether it will be approved and be made available to the public.

Standard of Care

The standard of care is the most accepted and standard treatment for a disease or condition. This may vary by country or region.

Tests and Assessments

You will undergo various tests and assessments during trial participation. The types of tests and assessments will depend on the trial, but these usually include vital signs measurements, physical exams, blood and urine sample collections, and questions about how you are feeling.

Trial Clinic Visits

You will be required to attend clinic visits, also called study visits, throughout a trial. The number of visits will depend on the trial, but at each clinic visit, the trial doctor and staff will perform various tests and assessments to monitor your health.

Trial Doctor

The trial doctor is in charge of the trial at a clinic. He or she will determine whether patients can be in a trial and whether they should continue in a trial. A trial doctor may also be called a study doctor or investigator.

Trial Sponsor

The trial sponsor, which is typically a pharmaceutical company, academic center, or non-profit organization, conducts a clinical trial and pays the trial doctor and staff to conduct the trial.


Participation in a clinical trial is your decision. That means you don’t have to participate if you don’t want to. Even if you participate, you can leave a trial at any time and for any reason.