Medical Studies
There are basically three types of studies involving human subjects. One of these is counting studies which are also known as population studies. Counting studies are statistical in nature and can link things to each other such as men who eat fish three times a week have lower cholesterol. However, these studies do not prove that that one causes the other.
Another study type is observing over time. These studies can follow a group or groups of people over a course of years or even decades. Similar to the counting study in the fact that link things like those who start exercising young and continue to do so have less heart disease. This type of study has the same shortfalls of a counting study, the only real difference is the data is accumulated over a period of time. This type of study also can not prove cause and effect.
The third type of study is known as manipulating studies. This type of study is looking at cause and effect. This type of study can also be called a clinical trial, clinical study or experimental study. This type of study gives some type of treatment like a medicine or herb and tests for results over a finite period of time.
From this point forward we will refer to manipulating studies as clinical trials. There are also a few sub types within this group. They are 1) placebo controlled (some patients receive a placebo rather than the actual medicine) 2) controlled (when one treatment is compared to another treatment) 3) blind (this is when the patients don’t know whether they are getting the placebo or the medicine) 4)generally a study is not designated as blind but as single blind (the doctor know who is getting which but the patients do not) or double blind (this is when neither the patients nor the doctor knows who is getting which). Lastly there are also some studies known as “open label” Open label studies do not use placebos and everyone knows that all participants are getting the medicine.
Tomorrow night I will write a post that discusses randomization (a common technique used in clinical trials). I will also discuss some of the potential draw backs of randomization.