A family member can go to one of two local hospitals for heart surgery. Checking the history for the past year, you find that each of the two hospitals has performed cardiac surgery on 1000 patients. In hospital A 710 patients survived (71%). In hospital B 540 (54%) survived. 1. Based on the numbers presented, which hospital do you think is superior in cardiac surgery? Now, let's look at the data in more detail breaking down the data by patient condition.

Patient Entering Condition	Hospital A	Hospital B	Survivors from A (# and percent)	Survivors from B (# and percent)
Fair	700	100	600 or 86%	90 or 90%
Serious	200	200	100 or 50%	150 or 75%
Critical	100	700	10 or 10%	300 or 43%
Total	1000	1000	710 or 71%	540 or 54%

2. Looking at the data broken down in this way, which hospital do you think is superior in cardiac surgery?

3. What was done differently with the data of the hospitals that changed the conclusion?

4. what does Simpson's Paradox mean to you?

4. What would you do if different statistical approaches lead to conflicting conclusions?