Question 1:
The following data were collected in a clinical trial to compare a new drug to a placebo for its effectiveness in lowering total serum cholesterol. Generate a 95% confidence interval for the difference in mean total cholesterol levels between treatments.
|
|
New Drug (n=75)
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Placebo (n=75)
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Total Sample (n=150)
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|
Mean (SD) Total Serum Cholesterol
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185.0 (24.5)
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204.3 (21.8)
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194.7 (23.2)
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% Patients with Total Cholesterol < 200
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78.0%
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65.0%
|
71.5%
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(-26.66, -11.94) or (11.94, 26.66)
(-29.00, -13.98) or (13.98, 29.00)
(-24.95, -11.25) or (11.25, 24.95)
(-28.75, -10) or (10, 28.75)
Question 2:
A clinical trial is run to investigate the effectiveness of an experimental drug in reducing preterm delivery to a drug considered standard care and to placebo. Pregnant women are enrolled and randomly assigned to receive either the experimental drug, the standard drug or placebo. Women are followed through delivery and classified as delivering preterm (< 37 weeks) or not. The data are shown below.
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Preterm Delivery
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Experimental Drug
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Standard Drug
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Placebo
|
|
Yes
|
17
|
23
|
35
|
|
No
|
83
|
77
|
65
|
Using this data, generate a 95% confidence interval for the difference in proportions of women delivering preterm in the experimental and standard drug treatment groups.
(-0.255, 0.02) or (-0.02, 0.255)
(-0.18, 0.09) or (-0.09, 0.18)
(-0.17, 0.05) or (-0.05, 0.17)
(-0.15, 0.10) or (-0.10, 0.15)
Question 3:
A clinical trial is run to evaluate the effectiveness of a new drug to prevent preterm delivery. A total of n=250 pregnant women agree to participate and are randomly assigned to receive either the new drug or a placebo and followed through the course of pregnancy. Among 125 women receiving the new drug, 24 deliver preterm and among 125 women receiving the placebo, 38 deliver preterm. Construct a 95% confidence interval for the difference in proportions of women who deliver preterm.
(-0.35, 0.07) or (-0.07, 0.35)
(-0.1, 0.09) or (-0.09, 0.1)
(-0.22, 0.00) or (0.00, 0.22)
(-0.43, 0.2) or (-0.2, 0.43)
The following table shows the distribution of BMI in children living in US and European urban neighborhoods. (The data are in millions.)
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Neighborhood
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Normal Weight
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Overweight
|
Obese
|
|
US
|
125
|
50
|
40
|
|
Europe
|
101
|
42
|
21
|
What proportion of children living in a European urban neighborhood is overweight?
Question 4: The following table shows the numbers of patients classified as underweight, normal weight, overweight and obese according to their diabetes status.
|
|
Underweight
|
Normal Weight
|
Overweight
|
Obese
|
|
Diabetes
|
8
|
34
|
65
|
43
|
|
No Diabetes
|
12
|
85
|
93
|
40
|
What proportion of normal weight patients is not diabetic?
Question 5: What is the best type of graph to display the following data?
Region of country: New England, New England, South, West, New England, Mid-Atlantic, Mid-Atlantic, New England, New England, South, New England, New England, Midwest, New England, Mid-Atlantic, Mid-Atlantic, New England, West
1)Boxplot
2)Scatterplot
3)Side-by-side boxplot
4)Bar graph
Is Bar graph the correct answer?