LSAT 113 | Section 3 | Logical Reasoning: Q6

LR Question 6 Explanation

QUESTION TEXT: It is proposed to allow the sale, without prescription, of…

QUESTION TYPE: Weaken

CONCLUSION: Most people can diagnose swimmer’s ear themselves without ever having to consult a physician.

REASONING: A survey of 1,000 people who suspected they had swimmer’s ear showed that 84% had made a correct diagnosis.

ANALYSIS: The sample is very biased. What about the people who have swimmer’s ear but don’t suspect that they have it?

You have to count them to in order to get the accuracy rate. It’s possible most people fail to diagnose swimmer’s ear, because they don’t suspect they have it.

The other possibility is that these people suspected that they had swimmer’s ear because they had already had it and seen a doctor (who told them what the disease was.)

The info in the first two sentences isn’t relevant to finding the correct answer. The conclusion is about the accuracy of self-diagnosis rates.

___________

1. This doesn’t affect the conclusion about self-diagnosis rates.
2. It doesn’t really matter what they thought. The main point is that 84% is a high percentage.
3. CORRECT. This shows that they had already learned what swimmer’s ear was from a physician. So they might need a physician after all, for the initial diagnosis. 
4. This doesn’t affect the fact that the public had a better rate than physicians in general. Few people will ever see a specialist for swimmer’s ear.
5. This tells us what happens when people get the disease. It doesn’t tell us how well people can diagnose the disease themselves.