The basics
What are clinical trials? Per the National Institutes of Health:
What are clinical trials and why would I want to take part?
Clinical trials are part of clinical research and at the heart of all medical advances. Clinical trials look at new ways to prevent, detect, or treat disease. Clinical trials can study:
- New drugs or new combinations of drugs
- New ways of doing surgery
- New medical devices
- New ways to use existing treatments
- New ways to change behaviors to improve health
- New ways to improve the quality of life for people with acute or chronic illnesses.
The goal of clinical trials is to determine if these treatment, prevention, and behavior approaches are safe and effective. People take part in clinical trials for many reasons. Healthy volunteers say they take part to help others and to contribute to moving science forward. People with an illness or disease also take part to help others, but also to possibly receive the newest treatment and to have added (or extra) care and attention from the clinical trial staff. Clinical trials offer hope for many people and a chance to help researchers find better treatments for others in the future
What is a Clinical Study? Per the University of California San Diego (USCD) School of Medicine:
A clinical study involves research using human volunteers (also called participants) that is intended to add to medical knowledge. There are two main types of clinical studies: clinical trials and observational studies.
Clinical Trials
In a clinical trial (also called an interventional study), participants receive specific interventions according to the research plan or protocol created by the investigators. These interventions may be medical products, such as drugs or devices; procedures; or changes to participants' behavior, for example, diet. Clinical trials may compare a new medical approach to a standard one that is already available or to a placebo that contains no active ingredients or to no intervention. Some clinical trials compare interventions that are already available to each other. When a new product or approach is being studied, it is not usually known whether it will be helpful, harmful, or no different than available alternatives (including no intervention). The investigators try to determine the safety and efficacy of the intervention by measuring certain outcomes in the participants. For example, investigators may give a drug or treatment to participants who have high blood pressure to see whether their blood pressure decreases.
Observational Studies
In an observational study, investigators assess health outcomes in groups of participants according to a protocol or research plan. Participants may receive interventions, which can include medical products, such as drugs or devices, or procedures as part of their routine medical care, but participants are not assigned to specific interventions by the investigator (as in a clinical trial). For example, investigators may observe a group of older adults to learn more about the effects of different lifestyles on cardiac health.
Study or Trial?
Do we refer to them as Studies or Trials? "Clinical studies" is a broader tern that includes observational studies. "Clinical trials" is narrower and inclues only interventional, as you can see in the image below. Image is from the MeSH database.
For the purposes of this guide, we will call them "studies" since we will discuss Observational studies as well.
ClinicalTrials.gov also considers "Clinical Studies" to be a broader category than "Clinical Trials." As they state on their website: "A clinical study involves research using human volunteers (also called participants) that is intended to add to medical knowledge. There are two main types of clinical studies: clinical trials (also called interventional studies) and observational studies."
University of California San Diego (UCSD) School of Medicine says the same; they state on their webpage: "What is a Clinical Study? A clinical study involves research using human volunteers (also called participants) that is intended to add to medical knowledge. There are two main types of clinical studies: clinical trials and observational studies.
Resources
References
National Center for Biotechnology Information, MeSH database.Clinical Study [Publication Type]. https://www.ncbi.nlm.nih.gov/mesh/2009830
National Institutes of Health.NIH Clinical Trials Research and You: The Basics. https://www-ncbi-nlm-nih-gov.ezproxy.rush.edu/mesh/2009830
National Institutes of Health, ClinicalTrials. gov. (2019). Learn about Clinical Studies. https://clinicaltrials.gov/ct2/about-studies/learn#WhatIs
University of California San Diego Medical School, Huntington Disease Clinical Research Center.Cliinical Studies Explained. https://medschool.ucsd.edu/som/neurosciences/centers/huntingtons-disease/research/Pages/clinical-observational-trials.aspx
