Trial basics, explained step by step

Types of studies

General Clinical Trials

Structured research studies that follow a protocol to answer defined questions. They range from short single-visit studies to long-term programs.

Observational Studies

Researchers watch and record what happens over time without assigning a specific approach. Volunteers often complete surveys or periodic check-ins.

Interventional Studies

Volunteers are assigned to a specific approach so researchers can compare results. Assignment is described in the protocol and consent document.

Health Research

Studies that explore how the body works, how conditions develop, or how care can be improved. Some focus on healthy volunteers.

Behavioral Research

Studies that look at habits, sleep, learning, stress, or daily routines. Many involve questionnaires, journals, or short sessions.

How a study generally unfolds

1. Step 1

   Before a study

   The study team publishes a summary, an ethics committee reviews the protocol, and volunteers can learn about the study and ask questions.

2. Step 2

   Getting started

   Volunteers review the consent document with the study team and decide whether to take part. There is no obligation to continue.

3. Step 3

   During a study

   Volunteers attend visits or complete tasks described in the protocol and can raise questions or concerns at any time.

4. Step 4

   After a study

   Some studies share general findings with volunteers. Ask the study team how and when results may be shared.