Question

Chronic obstructive pulmonary disease (COPD) is a lung disease that makes it difficult for people to breathe, since small airways in their lungs become blocked. This can make patients gasp for breath or breathe at a higher than usual rate to try to get oxygen. A common treatment for this problem is to have patients breathe oxygen through breathing tubes. We have a sample of COPD patients who naturally breathe at the same rate. Each patient walks on a treadmill for 5 minutes wearing an oxygen tube. Each of the 15 patients is given a slightly different concentration of oxygen, and at the end we calculate an average breath rate for each. What technique should we use to see if variation in oxygen concentration has a statistical effect on breath rate?

Question 40 options: 1-sample z test for proportions

1-sample t test

1-variable chi-square test

2-sample z test for proportions

2-sample t test

2-variable chi-square test

analysis of variance

correlation analysis

linear regression

Answer 1

The appropriate method is to use analysis of variance because here we have the factor as concentration of oxygen and it has 15 different levels as oxygen levels are different for each of 15 patients. So here we will proceed to test whether all the 15 means of breath rates are equal or not . If it is equal then we get the conclusion the treatments have significant effect and vice versa. As in analysis of variance method we use the mean test for different groups of one or two factors so here analysis of variance is appropriate.