Question

Research Designs

Researchers were interested in learning the effects of trans fats on levels of cholesterol in the blood. Two different research designs were constructed.

Part I: Between-Groups Design

In the between-groups design, researchers were interested in whether cholesterol levels would differ depending on diet. Twenty participants were randomly assigned to one of two different groups. Group A was assigned a diet rich in fruits and vegetables and with no trans fats. Group B participants were asked to follow their normal diets, which contained varying levels of trans fats depending on the individual. After one month, blood samples were drawn and the following levels of cholesterol were obtained:

Participant	Blood Cholesterol	Diet
1	129	Healthy
2	98	Healthy
3	150	Healthy
4	75	Healthy
5	135	Healthy
6	175	Healthy
7	115	Healthy
8	103	Healthy
9	156	Healthy
10	143	Healthy
11	239	Normal
12	500	Normal
13	350	Normal
14	468	Normal
15	198	Normal
16	213	Normal
17	225	Normal
18	175	Normal
19	560	Normal
20	289	Normal

In 2 to 3 sentences in a Microsoft Word document, answer the following questions:

What is the independent variable in this study?

What are the levels of that independent variable?

What is the dependent variable?

Submission Details:

Name this document SU_PSY2008_W5_A_LastName_FirstInitial

Create a data file that will enable you to conduct a between-groups analysis of this data.

Name your worksheet SU_PSY2008_W5_A_worksheet_LastName_FirstInitial

Part II: Within-Subjects Design

In the within-subjects design, researchers were interested in whether participants could lower their cholesterol levels by changing from a diet higher in trans fats to one with no trans fats. Ten research participants were selected. A baseline measure of cholesterol was taken from each. They were then put on a diet rich in fruits and vegetables and devoid of trans fats for one month. At the end of that month, blood cholesterol was again measured and the following results were obtained:

Participant	Blood Cholesterol	Diet
1	129	Baseline
1	98	Healthy
2	150	Baseline
2	75	Healthy
3	175	Baseline
3	135	Healthy
4	115	Baseline
4	103	Healthy
5	156	Baseline
5	143	Healthy
6	500	Baseline
6	450	Healthy
7	468	Baseline
7	350	Healthy
8	198	Baseline
8	213	Healthy
9	225	Baseline
9	175	Healthy
10	560	Baseline
10	481	Healthy

In 2 to 3 sentences in a Microsoft Word document, answer the following questions:

What is the independent variable in this study?

What are the levels of that independent variable?

What is the dependent variable?

Answer 1

Given that

In the between groups design, researchers were intrested in whether cholesterol levels would different depending on diet. Group B participants were asked to follow theri normal diets which contained varying levels of trans fats depending n the individual.

1. An independent variable is the variable that is changed or controlled in a scientific experiment.

Independent variables are the variables that the experimenter changes to test their dependent variable.

Here, The Diet influenced on Blood Cholesterol. So Indepdent variable is Diet.

2. There are two levels of Diet one is Healthy another one is Normal.

3. A dependent variable is the variable being tested in a scientific experiment.

The dependent variable is 'dependent' on the independent variable. As the experimenter changes the independent variable, the change in the dependent variable is observed and recorded.

Here Blood Cholesterol is influenced by Diet. So dependent variable is Blood Cholesterol

1. An independent variable is the variable that is changed or controlled in a scientific experiment.

Independent variables are the variables that the experimenter changes to test their dependent variable.

Here, The Diet influenced on Blood Cholesterol. So Indepdent variable is Diet.

2. There are two levels of Diet one is Healthy another one is Baseline.

3. A dependent variable is the variable being tested in a scientific experiment.

The dependent variable is 'dependent' on the independent variable. As the experimenter changes the independent variable, the change in the dependent variable is observed and recorded.

Here Blood Cholesterol is influenced by Diet. So dependent variable is Blood Cholesterol