An experimenter wants to study the relationship between caffeine and reaction time. She assigns participants as follows: Group One receives 100 mg of caffeine; Group Two receives 200 mg of caffeine; Group Three receives 300 mg of caffeine; and, Group Four receives no caffeine. Twenty minutes later all participants complete the reaction-time test. Which group is the control group?

Question

Quizplus · Accepted Answer

The control group in an experiment is the group that does not receive the treatment or intervention being studied. In this experiment, the treatment or intervention is the consumption of caffeine. Therefore, the control group is Group Four, which did not receive any caffeine, allowing the experimenter to compare their reaction times to the groups that did receive caffeine.

An Experimenter Wants to Study the Relationship Between Caffeine and Reaction