Question

Researchers randomly divide participants into groups. Each group takes a different amount of omega-3 fatty acid supplements daily for a month. One group receives a placebo. The researchers measure the impact on cholesterol levels in the blood. What is the purpose of random assignment in this experiment?

a. To ensure that all people with high cholesterol have an equal chance of being selected for the study
b. To increase the accuracy of the research results and prevent skewness in the data
c. To produce treatment groups with similar characteristics
d. To control confounding

Answer 1

b. To increase the accuracy of the research and prevent skewness in the idea.

Explanation:

Random assignment ensures that any difference between groups recorded at the end of an experiment can be attributed to the experimental procedures. It refers to how you arrange the participants into required groups (different treatment and control groups). In the case of non-random assignment, the two major problems are generalisation of results and bias, which could lead to skewness in the idea of the experiment.

One of the importance of random assignment in this given experiment is to increase the accuracy of the research and prevent skewness in the idea.