Understanding Studies, Part II
As promised yesterday, this is the second part of ASCO's Patient Net articles about reading and understanding research studies. Whether this is something you do often or rarely, it is truly worth reading these articles to improve your understanding. Even if you only read newspaper articles, it is helpful to know the language and to be an informed reader.
Here is an excerpt and then a link to read it all:
This article is the second in a two-part series designed to help you better understand cancer research. It outlines various types of study designs and provides tips for evaluating study results. Part I describes the publishing process, the format that journals and other scientific publications use to share findings, and how to find studies of interest to you.
Researchers can design medical studies in different ways, depending on the question they want to answer and the best way to answer it. No study design is perfect; each has strengths and drawbacks. When evaluating the results of a study, it is important to know its design so that you know if the results apply to your situation.
In cancer research, there are two main categories of research study design: Experimental studies
In an experimental study, researchers apply an intervention (such as a treatment) to a group of individuals, and compare the result to that of another group that does not receive the intervention. The researchers have control over who receives the intervention and who does not, making the assignments either randomly (for reasons explained below) or through intentional selection. Meanwhile, in an observational study the researchers observe groups in which the intervention that each person receives is not controlled by the researchers.