A control group in science is a group in an experiment that does not receive the treatment or the independent variable being tested. It serves as a baseline or standard for comparison to the experimental group, which does receive the treatment. By comparing outcomes between the control and experimental groups, scientists can isolate the effect of the independent variable and determine whether any changes are truly due to the treatment rather than other factors
. There are two main types of control groups:
- Negative control group: This group is not expected to show any effect and helps confirm that the experimental setup itself does not cause changes. For example, in drug testing, a negative control group might receive a placebo, which is an inactive substance
- Positive control group: This group is given a treatment known to produce the expected effect, ensuring the experiment is capable of detecting an effect. It validates the experimental procedure and provides a benchmark for comparison
In summary, the control group is essential in scientific experiments to establish causality, minimize bias, and provide a clear point of comparison to evaluate the true impact of the experimental treatment
