Two Groups When Testing a Hypothesis

The Scientific Method

• The scientific process begins with the steps of the scientific method. Scientists start with a research question, which is the problem the scientists want to solve. They formulate a hypothesis regarding the question and create an experiment to test that hypothesis. The result of the experiment is the conclusion. The conclusion is the results of the experiments, which may or may not support the hypothesis.

Control Group

• Every experiment has variables a scientist either doesn't account for or cannot control. Introducing an experimental factor to a system can cause numerous changes. The control group gives the scientist a way to show how the system would look without the experimental factor. The control group does not contain the experimental factor and goes through the experiment reacting as it would in nature.

Experimental Group

• The experimental group is the test group and is subject to the experimental factor. For example, in the case of a drug trial, the experimental group receives the drug and the control group does not. Scientists can observe whether the drug helps or harms those in the test group. If both groups show the same results, the scientist knows the results were not produced by the experimental factor.

Multiple Groups

• When scientists come up with a hypothesis, sometimes they have several variables they want to test. For example, if a behavioral study wants to determine how fast a person in trouble is helped, scientists may have one experimental group in which the person just collapses, and a second group in which the person has a cane. There can be several experimental groups in an experiment, but only one control group.