Bunuel
The average length of stay for patients at Edgewater Hospital is four days, compared to six days at University Hospital. Since studies show that recovery rates at the two hospitals are similar for patients with similar illnesses, University Hospital could decrease its average length of stay without affecting quality of care.
The reasoning in the argument is most vulnerable to criticism on the grounds that the argument
(A) equates the quality of care at a hospital with patients’ average length of stay
(B) treats a condition that will ensure the preservation of quality of care as a condition that is required to preserve quality of care
(C) fails to take into account the possibility that patients at Edgewater Hospital tend to be treated for different illnesses than patients at University Hospital
(D) presumes, without providing justification, that the length of time patients stay in the hospital is never relevant to the recovery rates of these patients
(E) fails to take into account the possibility that patients at University Hospital generally prefer longer hospital stays
EXPLANATION FROM Fox LSAT
This is a super-common concept on the LSAT. The problem here is selection bias. How do we know that Edgewater doesn’t treat mostly ingrown toenails, while University Hospital does mostly open heart surgery? If that were true, then it would be nonsensical to compare the average length of stay for the two hospitals.
A) We’re looking for something that suggests the two hospitals might have different ratios of difficult cases. This doesn’t do that.
B) This describes an error of conditional reasoning, but I didn’t see that error in the argument. This is out.
C) This is exactly what we predicted. Let’s read D and E just to be sure, but this is probably the one.
D) The argument doesn’t ever assume that length of stay is
never relevant to recovery rates. This is out.
E) The argument is not about what patients prefer… who cares about them?
Our answer is C, because it points out the potential problem with selection bias that we were looking for.