To test the effectiveness of a liquid supplement that is supposed to help forgetful people with their memory, 400 college students are recruited for a study and divided into two groups. Group A with 250 students receives the supplement, while group B with 150 students receives some colored water. Neither group is told what they received. After several weeks, they are given a memory test. This study can best be described as

This is a "CONTROLLED PLACEBO EXPERIMENT".

Explanation: A controlled placebo experiment is a type of research method that is used to check the effectiveness of a drug in a patient. This is done by selecting a sample group, then randomly divide the two group into a placebo group ( this are the group that will receive the drug treatment ) and the controlled group( these are the group that will receive a coloured mixture that looks like the drug, but does not have any effect). Without the groups knowledge about the real drugs and the coloured mixture, but are followed up and tested.

This is a controlled placebo experiment, because 400 student has been choosed as the sample, and are divided into a placebo group and a controlled group, to check the effectiveness of a drug on their memory.

Controlled placebo study

Explanation:

A controlled placebo study can be described as a method that is employed to test a medical therapy by creating two different groups in which the first group of subjects are given the treatment to be examined, while the second group receive a sham placebo treatment that is meant not to produce any effect.

The aim is to compare the results of the two types of test, note difference and then draw an empirical conclusion.

Therefore, the study described in the question is a controlled placebo study.

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