(QUESTION 6)A study was undertaken to evaluate the effect of percutaneous transluminal-coronaryangioplasty (PTCA) in patients with one-vessel coronary artery disease. A random sampleof one hundred and seven patients with coronary artery disease were given PTCA. Patientswere given exercise tests at baseline and after 6 months of follow-up. Exercise tests wereperformed up to maximal effort until symptoms (such as angina) were present. The "change"in the duration of exercise was calculated. "Change" is defined as the 6 month fest minus thebaseline test. The mean change was 2.1 minutes and the standard deviation of the changeswas 3.1.What statistical test can be performed to see if there has been a statisticallysignificant change in duration of exercise for this group of patients given PTCA?• Compute a 95% confidence interval for the mean change in exercise duration.●● Can we conclude from this study that PTCA is effective in increasing exerciseduration? Are there any limitations or weaknesses in this study for answering thatquestion?

Given: x¯=2.1s=3.1n=107α=0.05

Answered: A study was undertaken to evaluate the…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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