Scientists conduct a study in which 100 adults with chronic diarrhea are divided into 2 groups with 50 people per group.One group is given a supply of yogurt that contains a certain kind of bacteria,and the other group is given yogurt that is bacteria-free.The study's participants and researchers do not know which group of subjects has the bacteria in the yogurt and which group does not.The scientists instruct the participants to eat the entire 8 ounces of yogurt once a day for a month and record their bowel habits.This is an example of a(n)________ study.
A)introspective
B)double-blind
C)uncontrolled
D)hypothetical

Question

Quizplus · Accepted Answer

This study is a double-blind study because both the participants and the researchers do not know which group is receiving the yogurt with bacteria and which group is receiving the bacteria-free yogurt. This is done to prevent any bias or expectations from influencing the results.

Scientists Conduct a Study in Which 100 Adults with Chronic