Southside Hospital in bay shoreNew Yorkcommonly conducts str

Southside Hospital in bay shore,New York,commonly conducts stress tests tostudy the heart mauscle after a person has a heart attac. Members of the diagnostic imaging department conduct a quality improvemeny project with the objective of reducing the turnaround time for stress tests.Turn around time is defined as the time form when a test is ordered towhen the radiologist signs off on the testresults.Initially,the mean turnaround time for a stress testwas 68 hours. After incorperating changes into the stress-test process,the quality improvement team collected a sample of 50 turn around time. In this sample,the mean turnaround was 32, with a standard deviation of 9 hours .

a If you test the null hypothesis at .01 levelof significants, is there evidentce that the new process has reduced the turnaroundtime

interpret the meaning of the p-value inthis problem

( answers and excel help needed)

Solution

H0: mu = 68

Ha: mu < 68

Left tailed test.

Sample mean = 32

Mean differnce = 32-68 = -36

Std error = 9/rt 50 = 1.273

z statistic = -28.28

p value = 0

As p is negligible, reject null hypothesis.

The p value =0 indicates that prob of incorrect rejecting true null hypothesis is only 0.00