Question
You are testing the effect of a new drug to treat severe viral pneumonia. To do this you conduct a randomized controlled trial (RCT). You enroll 200 participants in your study; 100 are allocated to the intervention arm (they receive the drug) and 100 receive the current standard of care. 9 of the participants in the intervention arm and 16 of the participants in the standard care arm die of pneumonia.
a. Draw a contingency table to represent these data.
b. What is the probability (p) of death among the intervention group?
c. What are the odds of death among the intervention group?
d. What is the odds ratio (OR) comparing the intervention group to the control group?
e. Calculate the appropriate relative risk (RR) measure from these data.
f. What does this demonstrate about how the OR and the RR differ when calculated using the same data?
g. Calculate the variance of the log (ln) of both the odds ratio and the RR you calculated in part d.
