4. A preliminary study conducted at a medical center in St. Louis has shown that treatment with small. low-intensity magnets reduces the self-reported level of pain in polio patients. During each session, a patient rested on an examining table in the doctor's office while the magnets, embedded in soft pads, were strapped to the body at the sit of pain. Sessions continued for several weeks, after which pain reduction was measured. A new study is being designed to investigate whether magnets also reduce pain in patients suffering from hemiated disks in the lower back. One hundred male patients are available for the new study. (a) Describe an appropriate design for the new study. Your discussion should briefly address treatments used, methods of treatment assignment, and what variables would be measured. Do not describe how the data would be analyzed. (b) Would you modify the design above if,instead of 100 male patients, there were 50 male and 50 female patients available for the study? If so how would you modify your design? If not,why not? 5. A random sample of students at a particular high school was asked if they felt the state spent enough money of public parks.Eighty percent of the student responded that the state did not spend enough money. Which of the following conclusions is valid? (A) High school students across the state probably feel the same. (B) High school students in the same district probably feel the same. (C) The parents of the students probably feel the same. (D) Students at the same high school that were not interviewed probably feel the same. (E) All of these conclusions are valid.

## Step 1<br />The first part of the question asks for an appropriate design for a new study. The study is about the effectiveness of low-intensity magnets in reducing pain in patients suffering from herniated disks in the lower back. The design should include the following elements:<br /><br />### **Treatments used**: The treatment used in this study is the application of low-intensity magnets.<br /><br />### **Methods of treatment assignment**: The patients should be randomly assigned to either the treatment group (those who receive the magnets) or the control group (those who do not receive the magnets).<br /><br />### **Variables to be measured**: The primary variable to be measured is the level of pain in the patients. This can be measured using a pain scale or similar tool.<br /><br />## Step 2<br />The second part of the question asks if the design would be modified if the study included both male and female patients. The answer is no, the design would not be modified. The reason is that the gender of the patients does not affect the effectiveness of the treatment. The treatment is based on the application of magnets, which should work equally well on both male and female patients.<br /><br />## Step 3<br />The third part of the question asks which conclusion is valid based on the survey results. The survey shows that 80% of the students believe the state does not spend enough money on public parks. The only valid conclusion that can be drawn from this is that students at the same high school that were not interviewed probably feel the same. This is because the survey only includes students from one high school, and it is reasonable to assume that the opinions of the students who were not interviewed would be similar to those who were.