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Chapter 4: Q 61. (page 255)

Headache relief Doctors identify “chronic tension- type headaches” as headaches that occur almost daily for at least six months. Can antidepressant medications or stress management training reduce the number and severity of these headaches? Are both together more effective than either alone? Investigators compared four treatments: antidepressant alone, placebo alone, antidepressant plus stress management, and placebo plus stress management. The headache sufferers named in the following table have agreed to participate in the study.

(a) Outline the design of the experiment. What is this type of design called?

(b) Explain how you would randomly assign the subjects to the four treatment groups. Then carry out your random assignment.

Short Answer

Expert verified

(a) This design is called total randomized design.

(b) It is possible by way of slips of paper.

Step by step solution

01

Given Information

Here, we want to check the effectiveness of antidepressant, medications or stress management training in reducing chronic tension type headaches when used daily for six months.

The headache sufferers are:

02

To identify experimental design

The treatments are distributed by chance to all in total randomized system.

Description is

03

To explain how to randomly assign the subjects to the four treatment groups.

  • The subjects can be assigned randomly to four treatment classes.
  • To implement the concept, thirty six slips are created to execute the concept.
  • Shake it well and take out nine slips. Assign first treatment class to them.
  • Take out other nine slips and assign them second treatment class.
  • Repeat till for all four treatment classes.

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