LSAT Explanation PT 35, S4, Q24: A recent study of 6,403 people

LSAT Question Stem

The argument's reasoning is flawed because the argument 

Logical Reasoning Question Type

This is a Flaw question. 

Correct Answer

The correct answer to this question is B. 

LSAT Question Complete Explanation

Let's first analyze the argument in the passage. The passage presents a study of 6,403 people, which found that those treated with pravastatin (a drug that reduces cholesterol) had fewer nonfatal heart attacks and deaths from coronary disease than those not taking the drug. The passage also mentions that people with heart disease often have higher than average cholesterol levels. Based on these findings, the author concludes that lowering cholesterol levels reduces the risk of heart disease.

In this argument, the premises are:

1. The study showed that those treated with pravastatin had fewer heart attacks and deaths from coronary disease.

2. People with heart disease often have higher than average cholesterol levels.

The conclusion is:

Lowering cholesterol levels reduces the risk of heart disease.

To better understand the argument, let's use a simple example. Imagine a study that finds people who wear sunscreen have fewer sunburns than those who don't. Additionally, people with sunburns often have higher exposure to sunlight. Based on these findings, one might conclude that using sunscreen reduces the risk of sunburns.

An "Evaluate" question for this argument could be: "Does pravastatin reduce the risk of heart disease solely because of its cholesterol-lowering effect?"

The question type is a Flaw question, asking us to identify the flaw in the argument's reasoning. The correct answer is B.

Now let's discuss each answer choice:

a) The argument neglects the possibility that pravastatin may have severe side effects.

While this answer choice is true, it doesn't address the flaw in the argument's reasoning. The argument is about the relationship between cholesterol levels and heart disease, not the side effects of pravastatin.

b) The argument fails to consider that pravastatin may reduce the risk of heart disease but not as a consequence of its lowering cholesterol levels.

This is the correct answer. The argument assumes that the reduction in heart disease risk is solely due to the cholesterol-lowering effect of pravastatin, without considering other possible factors. It's like saying sunscreen reduces the risk of sunburns only because it blocks sunlight, without considering other factors like skin type or time spent in the sun.

c) The argument relies on past findings, rather than drawing its principal conclusion from the data found in the specific study cited.

The argument does draw its conclusion from the specific study cited, as well as mentioning that the findings are consistent with other studies. This answer choice doesn't identify a flaw in the argument's reasoning.

d) The argument draws a conclusion regarding the effects of lowering cholesterol levels on heart disease, when in fact the conclusion should focus on the relation between pravastatin and cholesterol levels.

This answer choice is incorrect because it suggests that there is a specific conclusion the argument should have focused on. However, authors have the freedom to choose what they want to focus on as long as it doesn't overlook a glaring error in the argument. The passage already mentions the relationship between pravastatin and cholesterol levels, so this answer choice doesn't identify a flaw in the argument's reasoning.

e) The argument fails to consider what percentage of the general population might be taking pravastatin.

This answer choice is irrelevant to the argument's reasoning. The argument is about the relationship between cholesterol levels and heart disease, not the prevalence of pravastatin use in the general population.