Homework Help is Here – Start Your Trial Now!
Math
Statistics
ventricular mass (LVM) i sequent cardiovascular dis ess the relationship betwe ls and LVM in children a grams. The goal is to strat

ventricular mass (LVM) i sequent cardiovascular dis ess the relationship betwe ls and LVM in children a grams. The goal is to strat

MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
See similar textbooks
icon
Related questions
Question
100%

Please only answer 7.58

**Cardiovascular Disease, Pediatrics** Left ventricular mass (LVM) is an important risk factor for subsequent cardiovascular disease. A study is proposed to assess the relationship between childhood blood pressure levels and LVM in children as determined from echocardiograms. The goal is to stratify children into a normal bp group (< 80th percentile for their age, gender, and height) and an elevated bp group (≥ 90th percentile for their age, gender, and height) and compare change in LVM between the 2 groups. Before this can be done, one needs to demonstrate that LVM actually changes in children over a 4-year period. To help plan the main study, a pilot study is conducted where echocardiograms are obtained from 10 random children from the Bogalusa Heart Study at baseline and after 4 years of follow-up. The data are given in Table 7.6. **7.56** What test can be used to assess if there is a change in mean LVM over 4 years?
Transcribed Image Text:**Cardiovascular Disease, Pediatrics** Left ventricular mass (LVM) is an important risk factor for subsequent cardiovascular disease. A study is proposed to assess the relationship between childhood blood pressure levels and LVM in children as determined from echocardiograms. The goal is to stratify children into a normal bp group (< 80th percentile for their age, gender, and height) and an elevated bp group (≥ 90th percentile for their age, gender, and height) and compare change in LVM between the 2 groups. Before this can be done, one needs to demonstrate that LVM actually changes in children over a 4-year period. To help plan the main study, a pilot study is conducted where echocardiograms are obtained from 10 random children from the Bogalusa Heart Study at baseline and after 4 years of follow-up. The data are given in Table 7.6. **7.56** What test can be used to assess if there is a change in mean LVM over 4 years?
**Table 7.6**: Pilot Data on Left Ventricular Mass (LVM) in Children from the Bogalusa Heart Study | ID | Baseline LVM (g) | 4-year LVM (g) | Change (g)* | |----|-----------------|---------------|-------------| | 1 | 139 | 163 | 24 | | 2 | 134 | 126 | -8 | | 3 | 86 | 142 | 56 | | 4 | 98 | 96 | -2 | | 5 | 78 | 111 | 33 | | 6 | 90 | 108 | 18 | | 7 | 102 | 167 | 65 | | 8 | 73 | 82 | 9 | | 9 | 93 | 77 | -16 | | 10 | 162 | 172 | 10 | **Mean**: Baseline LVM: 105.5 g 4-year LVM: 124.4 g Change: 18.9 g **Standard deviation (sd)**: Baseline LVM: 29.4 4-year LVM: 35.2 Change: 26.4 *Note: 4-year LVM minus Baseline LVM ### Statistical Analysis: **7.57**: Implement the test in Problem 7.56 and provide a two-tailed *p*-value. **7.58**: Provide a 95% confidence interval (CI) for the change in LVM over 4 years based on the data in Table 7.6. **7.59**: Since this was a pilot study, the main question of interest is how many subjects would be needed to detect an increase of 10 g in mean LVM over 4 years using a two-sided test with α = 0.05 and power = 80%. *Hint*: Assume that the estimated variance of change in LVM in the pilot study is the true variance of change in LVM.
Transcribed Image Text:**Table 7.6**: Pilot Data on Left Ventricular Mass (LVM) in Children from the Bogalusa Heart Study | ID | Baseline LVM (g) | 4-year LVM (g) | Change (g)* | |----|-----------------|---------------|-------------| | 1 | 139 | 163 | 24 | | 2 | 134 | 126 | -8 | | 3 | 86 | 142 | 56 | | 4 | 98 | 96 | -2 | | 5 | 78 | 111 | 33 | | 6 | 90 | 108 | 18 | | 7 | 102 | 167 | 65 | | 8 | 73 | 82 | 9 | | 9 | 93 | 77 | -16 | | 10 | 162 | 172 | 10 | **Mean**: Baseline LVM: 105.5 g 4-year LVM: 124.4 g Change: 18.9 g **Standard deviation (sd)**: Baseline LVM: 29.4 4-year LVM: 35.2 Change: 26.4 *Note: 4-year LVM minus Baseline LVM ### Statistical Analysis: **7.57**: Implement the test in Problem 7.56 and provide a two-tailed *p*-value. **7.58**: Provide a 95% confidence interval (CI) for the change in LVM over 4 years based on the data in Table 7.6. **7.59**: Since this was a pilot study, the main question of interest is how many subjects would be needed to detect an increase of 10 g in mean LVM over 4 years using a two-sided test with α = 0.05 and power = 80%. *Hint*: Assume that the estimated variance of change in LVM in the pilot study is the true variance of change in LVM.
Expert Solution
Step 1

Q 7.58

Statistics homework question answer, step 1, image 1

sample size,n= 10

Mean (d̄) =Σd/n  =189/10 = 18.9

standard deviation,Sd=√Σ(d-d̄)2)/n-1)  = √ 6282.9000/(10-1)    = 26.4

 

 

steps

Step by step

Solved in 2 steps with 2 images

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman
SEE MORE TEXTBOOKS