In a study on possible mealinduced hypoxemia in asymptomatic

In a study on possible meal-induced hypoxemia in asymptomatic patients with COPD (chronic obstructive pulmonary disease), arterial blood gas samples were drawn from patients immediately before and again 30 minutes after the initiation of feeding through nasogastric tubes. In each sample oxygen partial pressure was measured in mm Hg. The data are given below.

before60 83 87 52 86 95 59 101 80 91 89

after 62 85 85 50 84 93 58 99 77 88 82

Is meal-induced hypoxemia present on average in patients with COPD? I.e. is there on average a decrease in oxygen partial pressure in such patients\' blood as a result of feeding? Test an

appropriate hypothesis in order to answer the question.
(a) Write down the null and alternative hypotheses in mathematical symbols.
(b) Carry out the paired t test using Minitab.
(c) What are you assuming about the data by employing the paired t test. Verify your assumption using probability plot.
(d) Give your decision about the test at each of the three \"standard\" significance levels of 0.10, 0.05, and 0.01.
(e) Give your conclusion in the context of research.

Solution