One of the section leaders forwarded the question and answer below, which I am sharing with others, in case they have the same questions.
Q: I am writing regarding the current homework assignment #7. A few questions came up for me as I have been completing the assignment that I was hoping to be able to run by you.
For question 7-13
- part b: b) Figure (b) is the calibration plot for CURB65 (note the letter “U”). CURB 65 assigned only 3 patients to its highest risk group. How many of them died?
I ... am assuming that the bars represent the people who have died at each quintile. However, I do not remember being introduced to this type of representation of the bars along the bottom and am not sure that I am interpreting this correctly.
***A: You are correct in that you were not introduced to the bars below. Please focus on the curves themselves and the axis labels.
- part f: f) The authors were interested in a rule that could identify pneumonia patients at such low risk of death that they could be discharged from the emergency department. Even after re-calibration, only one of the 3 rules could identify patients at low enough risk to send home. Which of the 3 rules was it? Explain how you know.
(TN: The question included the student's answer, so I am deleting it.)
***A: Remember what you want with a safe test—something that captures all that could **even possibly** have the disease.
TN: Hope this helps. Please don't be shy about posting your questions to the forum! That way if you clear something up that confused others, they can thank you!
Tom