Trials of drugs
Some clinical trials involve healthy subjects with no pre-existing medical conditions. Other clinical trials pertain to people with specific health conditions who are willing to try an … See more

A fundamental distinction in evidence-based practice is between observational studies and randomized controlled trials. Types of … See more

A clinical trial produces data that could reveal quantitative differences between two or more interventions; statistical analyses are used to determine whether such differences are true, result from chance, or are the same as no treatment (placebo). Data … See more

Development
Although early medical experimentation was performed often, the use of a control group to provide an accurate comparison for the demonstration … See more

Clinical trials are classified by the research objective created by the investigators.
• In an observational study, the investigators observe the subjects and measure their outcomes. The researchers do not actively manage the study.
• In … See more

Clinical trials designed by a local investigator, and (in the US) federally funded clinical trials, are almost always administered by the researcher who designed the study and applied for the grant. Small-scale device studies may be administered by the … See more

Clinical trials are closely supervised by appropriate regulatory authorities. All studies involving a medical or therapeutic intervention on … See more