Q71 - When several of a dermatologist's patients complained

[martintp]

Can someone why D is right instead of b? I thought b is pretty irrelevent because we dont care about the contact with other devices arnt we trying to prove that "rash was caused by prolonged contact with phones" or are we trying to prove "that the cause was some kind of external contact"?

[timmydoeslsat]

This title can be renamed or edited to read "Q13 - When several of a dermatologist's patients..."

You can treat the stimulus in this question as an argument. The author goes from a correlation to causation, which is most definitely flawed reasoning.

The word cause on the LSAT should put you on high alert! Cause is such a difficult thing to determine. It takes evidence and science to prove cause. Think of the commercials you see on TV where side effects were reported and it is not certain IF THE MEDICATION CAUSED those symptoms. There is definitely a correlation there, but cause is something tough to determine.

The dermatologist in this case goes from "Well, you have a rash on just one side of your face. Well, I suspect it is some from external contact. It was also determined that the rash was prevalent on the side of the face that they used a telephone.

This certainly helps this to become more likely, but still not enough.

The dermatologist concludes that not only is the telephone the cause, but that it was prolonged contact!

The question stem is asking us for an answer that does not support this diagnosis. So, four of the answer choices will support the correlation to cause, but one will not.

A) This idea makes the conclusion more likely because now we have a reason why the telephone could cause a rash. An allergy.

B) This is a crucial reason. If contact was not the same on both sides of the face and other devices, it could be this other device that is THE CAUSE OF THE RASH! Think about it, if patient A of this dermatologist also used a scanner near his or her ear as if it were like a phone, then this could be the cause. With this answer choice, it is saying that no matter if it was a scanner, iPOD, iPAD, or iWHATEVER, it was used equally on each side, thus a rash would not be expected to be on just one side.

C) This addresses the prolonged contact with telephones issue. This gives us more ammo from correlation to cause.

D) At first glance, this seems attractive. However, this answer choice gives us nothing about prolonged contact.

E) This is a really strong boost to the diagnosis. This supports the doctor's diagnosis as this is what would be expected if prolonged contact with the telephone is the cause.