Experimental and Control Groups Explained

Experimental and control groups are used extensively by medical and psychological research personnel and also by people taking surveys. They are used with all sorts of things not just people. Animals, plants, and especially chemicals provide answers to the questions that people want to know. Sometimes, people take the treatment at their home, but researchers may test the participants from an office. Examples of this are different forms of therapies. Depending on the test, day or night the participants take the treatment.  Understanding the effects of substances, techniques, and events all are reasons for using experimental and control groups.

At least two groups participate. The control group is a group that does not receive a pill or stimulus. These types of groups help the researcher to achieve a more impartial result. Sometimes researchers will choose subjects that fit a specific mold. Control groups take away this tendency.

The experimental group is the group that receives the medication, treatment, or activity. This group experiences many of the ill or the beneficial effects of the treatment. Doctors or researchers pay particular attention to this group and usually watch for other positive or negative signs to the participants. The group has two, or less likely, three conditions to meet.  

At the end of the experiment, researchers analyze the differences between the control group and the experimental group. The difference (or similarities) between the two groups reveal how successful the substance, technique or event was. An example of a result is a study done in 2005 by Stanford University, ABC News and USA Today where research found that almost 1 in 5 Americans suffer from chronic pain. Researchers and doctors test new drugs and treatments this way.

The area of pure science uses these groups far more than any other area. However, social sciences also use them in test behavioral techniques and treatments in people wanting to lose weight, change their self image, and make lifetime changes.

With this type of research, the research manipulates those in the experimental group to see how the group members will respond. This research has a few different variations including randomized control trials, Solomon four-group design, and a few others. With randomized controls, a researcher takes samples and compares them to the experimental group. Solomon four-group design includes a pre-test and post-test. Four groups participate. One group takes the test. The other group does not. The researcher tests the effect of the test on the groups.

One of the main reasons for experimenting is to bring more satisfaction to our way of life. By learning how group members respond to stimuli, better products and services appear and help to achieve health and wellness.