LSAT Explanation PT 41, S1, Q5: Statistician: Two major studies found no

LSAT Question Stem

Which one of the following most accurately expresses the main conclusion of the statistician's argument? 

Logical Reasoning Question Type

This is a Main Conclusion question. 

Correct Answer

The correct answer to this question is B. 

LSAT Question Complete Explanation

In this passage, the statistician is arguing that the two major studies that found no causal link between medical procedure X and disorder Y are flawed. The structure of the argument is as follows:

Premise: One study looked at 1,000 people who had undergone procedure X, and the other study looked at 1,100 people who had undergone procedure X.

Premise: Disorder Y occurs in only .02 percent of the population.

Premise: Researchers would need to include many more than 1,100 people in a study to detect even a doubling of the rate of disorder Y.

Conclusion: The two studies are flawed.

The question type is Main Conclusion, which asks us to identify the main conclusion of the statistician's argument.

Now, let's analyze each answer choice:

a) Contrary to the findings of two major studies, there is reason to think that procedure X causes disorder Y.

- This answer choice is incorrect because the statistician does not claim that there is a causal link between procedure X and disorder Y, only that the studies are flawed.

b) Two studies that discovered no causal link between procedure X and disorder Y are unsound.

- This answer choice is correct because it accurately expresses the main conclusion of the statistician's argument: the two studies are flawed.

c) Researchers should conduct more-extensive studies of procedure X to determine whether the procedure is causally linked with disorder Y.

- This answer choice is incorrect because it is prescriptive (using "should") and not the conclusion made in the argument. The statistician does not recommend more extensive studies, but rather points out flaws in the existing studies.

d) The two studies cited did not reach a conclusion as to whether disorder Y results from procedure X.

- This answer choice is incorrect because the two studies did reach a conclusion (that there is no causal link between procedure X and disorder Y). The statistician's argument is about the flaws in these studies, not about their lack of conclusion.

e) Despite the opinions of many medical experts, it has not been established that there is a causal link between procedure X and disorder Y.

- This answer choice is incorrect because it focuses on the opinions of medical experts and the lack of established causal link. The main conclusion of the statistician's argument is about the flaws in the two studies, not about the lack of established causal link.

In summary, the correct answer is B, which accurately expresses the main conclusion of the statistician's argument: the two studies that discovered no causal link between procedure X and disorder Y are flawed.