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Chapter 4: Q 3.1. (page 244)

In an interesting experiment, researchers examined the effect of ultrasound on birth weight. Pregnant women participating in the study were randomly assigned to one of two groups. The first group of women received an ultrasound; the second group did not. When the subjects’ babies were born, their birth weights were recorded. The women who received the ultrasounds had heavier babies.

Did the experimental design take the placebo effect into account? Why is this important?

Short Answer

Expert verified

The concept did not recognize the placebo effect.

Step by step solution

01

Given information

Pregnant women participating in the study were randomly assigned to one of two groups

02

Concept

A placebo is an inactive treatment, sometimes called a 'sugar pill.

03

Explanation

The placebo effect was not included in the concept.

The placebo is a supportive therapy that has no "real" influence on the dependent variable, and the placebo effect is defined as a participant's favorable response to the placebo.

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