- Glossary of Terms
Glossary of Terms
We know that many of the concepts used on this site can be difficult to understand. For that reason, we have provided you with a glossary to help you make sense of the terms used in Comparative Effectiveness Research. Every word that is defined in this glossary should appear highlighted throughout the Web site. When you come upon a highlighted term and would like to read the full definition, you can either click on the word to visit the glossary or roll your mouse over the word for a pop-up definition.
Definition: An inactive substance commonly called a "sugar pill." In a clinical trial, a placebo is designed to look like the drug being tested and is used as a control. It does not contain anything that could harm a person.
For example, a group of studies showed that 54 percent of people using topical capsaicin for arthritis pain relief had skin irritation, compared to 15 percent of people using placebo. The placebo was a cream that looked identical to topical capsaicin but was made with inactive ingredients that had no potential for producing irritation.