Question

19.7 Clinical progression of SARS. Severe acute respiratory syndrome (SARS) is a viral respiratory illness that was first reported in Asia in 2003 and then spread worldwide to near pandemic levels before eventually being contained. A study examined a random sample of 75 patients diagnosed with SARS to describe the disease's clinical progression. One finding was that, while fever and pneumonia initially improved after treatment in all 75 956 patients, 64 patients developed recurrent fever. Explain why we can't use the

1. The plus four method adds four observations,two successes and two failures. What are the sample size and the count of successes after you do this? What is the plus four estimate p of the proportion p in the population of patients treated for SARS who develop recurrent fever?

2. Give the plus four 95% confidence interval for p.

Answer 1

After using the plus four method the sample size will be 79 and the number of successes will be 68. The estimate of plus four proportion will be p 68 79 = 0.86 It is known that the Z score for a 95% confidence level is 1.96. Hence, the calculation of the confidence interval is as shown below: Þ(1-7) CI = pzal 10.86(1-0.86) = 0.86–1.96 79 = (0.78.0.94) Therefore, the 95% confidence interval is 0.78 to 0.94. If you have more questions you can send them to us and we will try our best to help you out. Good luck with your studies!!!