In a yearlong study, half of the participants were given a simple kit

Question

In a yearlong study, half of the participants were given a simple kit to use at home for measuring the cholesterol level of their blood. They reduced their cholesterol levels on average 15 percent more than did participants without the kit. Participants were selected at random from among people with dangerously high cholesterol levels.

Which one of the following, if true, most helps to explain the study’s finding?

(A) The lower a blood-cholesterol level is, the less accurate are measurements made by the kit.

(B) Participants with the kit were more likely to avoid foods that lower cholesterol level.

(C) Participants with the kit used it more frequently during the first two months of the study.

(D) All the participants in the study showed some lowering of cholesterol levels, the most striking decreases having been achieved in the first three months.

(E) Participants using the kit reported that each reading reinforced their efforts to reduce their cholesterol levels.

adkikani · Answer

eakabuah   VeritasKarishma   MentorTutoring

How can I resolve the paradox in passage?

Situation: Half of participants who were given simple kit to measure blood level cholesterol
found the level to be decreased than participants who were not given the measuring kit.
Conflict: Still a random survey from people found higher cholesterol levels.

Can I assume the last sentence refer to the people who were given measuring kit?

How does this explain rise in level of cholesterol? I was not able to infer correct paradox it seems.

AndrewN · Answer

In the interest of helping the community, specifically  adkikani , who called my attention to the question, I will offer my thoughts below. As I like to do, I start CR questions by examining the question first.

Since I have not read the passage yet, I cannot surmise what lies in store. I just know know that whatever the outcome of the study, I need to find something  to explain  that result. Thus, I know I need to pay particular attention to the  finding .

This is one of the more straightforward CR passages:

Sentence 1 tells us the duration of the study, one year, as well as the proportion of participants, one half, that received  a simple kit... for measuring... cholesterol .

Sentence 2 reveals that the half of the participants  with  kits  reduced their cholesterol levels  by a greater percent than did the group   without  the kit .

Sentence 3 provides information about the selection process for the experiment, indicating that participants were  people with dangerously high cholesterol levels .

With this information sorted out, we need to find a plausible reason to explain Sentence 2 above. Why might the group with cholesterol-measuring kits have outperformed the group without kits, in terms of reducing their cholesterol levels?

Analysis: Nowhere does the passage discuss the accuracy of any measurements taken, so this answer is pure speculation.

Analysis: First off, we do not have any information about the dietary preferences of any group in the study, so this answer choice is off-base; furthermore, participants  with  the kit ended up reducing their average cholesterol levels by a  greater  amount than the group without the kit, so why would it follow that the former group would have  avoided  cholesterol-lowering foods? If foods were part of the passage at all, we would expect the answer to say the opposite, that the group  without  the kit was more likely to avoid such foods, based on the results or findings.

Analysis: How could we tell anything about when participants were or were not using their kits? The only temporal cue in the passage is  yearlong . No information can help us sort out one month or cluster of months from any other within that year.

Analysis: This is clear garbage, employing common CR traps in absolute statements-- all the participants --and superlatives-- most striking . We have no idea whether all participants improved their cholesterol levels. Perhaps some did, while others did not. We only get a relative comparison between groups, those with the kit versus those without, and we only get an  average  at that, so individuals within either group could have increased or decreased their cholesterol levels. We simply do not know. If that were not enough to see off this answer choice, we then get this problematic  first three months  bit at the end, and once again, we cannot tell any months apart from any others within the year the study was conducted.

Analysis: Which group of participants does the passage tell us  reduced their cholesterol levels  by a greater amount? Answer: the group that was  given a simple kit...  So if the kit-users found motivation through  each reading  to redouble their efforts and lower their cholesterol, then it would logically fit that this half of the participants had ended up reducing their cholesterol levels by a greater amount than their kit-less counterparts. Could this be the only reason for the findings? No, not at all. But it does provide exactly what the question asks us, an answer that  helps to explain the study's finding . Nothing is out of scope, and the right group and result is mentioned. This is a clear winner.

If anyone has further questions, I would be happy to help out. Good luck with your studies.

- Andrew

KarishmaB · Answer

Participants were selected at random from among people with dangerously high cholesterol levels
Half were given a simple kit to use at home for measuring the cholesterol level of their blood. 
Finding of the Study: They reduced their cholesterol levels on average 15 percent more than did participants without the kit.

How do we explain the finding? Why did people with the kit reduce their cholesterol by much more? Note that there is no paradox here. We just have some results and we need explanation for those.

(A) The lower a blood-cholesterol level is, the less accurate are measurements made by the kit.

We know that all participants had very high cholesterol to begin with. So measurements would be accurate. Accuracy would be low when the cholesterol level is low.

(B) Participants with the kit were more likely to avoid foods that lower cholesterol level.

This is against our argument. People with kits avoided good foods. Then they should not have seen a better decrease of cholesterol.

(C) Participants with the kit used it more frequently during the first two months of the study.

Irrelevant. It doesn't explain why they reduced their cholesterol more.

(D) All the participants in the study showed some lowering of cholesterol levels, the most striking decreases having been achieved in the first three months.

Again, irrelevant when the most decrease happened.

(E) Participants using the kit reported that each reading reinforced their efforts to reduce their cholesterol levels.

Right. The kit provided motivation. When the kit showed reduction, it reinforced their efforts (of reducing cholesterol). They got motivated to put in more effort to reduce. This explains why their cholesterol decreased much more.

Answer (E)

adkikani · Answer

Thank you  VeritasKarishma  and  MentorTutoring

I could understand my gaps w.r.t. your approach and would like to share the same
to improvise my learning.

The main point here is: People who were  given   measuring kits to monitor cholesterol levels actually  reduced 
their cholesterol  without  any external support (e.g exercising / medicines, apologize for going off tangent here) 
than the group of people who were not given monitoring kit.

This is the part where I got confused and misinterpreted. People are selected at random (from a group that was given measuring kit and a group that was not given measuring kit) and the reports showed HIGH levels of cholesterol. Where is this passage are we talking about CAUSES that led to HIGH levels of cholesterol?
How would you put last sentence in the context of the passage?

KarishmaB · Answer

There is no discussion on "causes" of high cholesterol level. All the participants of the study had dangerously high cholesterol levels. The group of people with dangerously high cholesterol levels was identified (say from the hospital records) and some were selected randomly from that for the study. 
Out of the ones selected for study, half were given kits and half were not. Note that ALL of them had dangerously high cholesterol levels.

AndrewN · Answer

Hello again,  adkikani . Although  VeritasKarishma  has already posted a fine response, I did want to address the second question a bit more. All the last sentence of the passage tells is some background information about the how the experiment was conducted. This process happens all the time in human health experiments. The researchers will say something like,  Okay. What if we took people with high cholesterol and gave half the participants this kit they can use at home to measure their cholesterol? Will they show any drop in cholesterol compared to a control group?  That control group, of course, is the group  not  given the kit. In order not to have any sort of eye on the outcome of the experiment, or in other words influence the outcome in any way, the researchers randomize the participants so that they, the researchers, have no idea who has gotten kits and who has not. In this manner, after the yearlong trial when the researchers are simply looking at the data, they say,  Patient X showed a such-and-such percent decrease.  And they can then look up whether that patient had belonged to the kit group or the one without. Because of the randomization process, the researchers can be more confident in the findings of the unbiased experiment. So in short, the researchers in the passage probably sought out high-cholesterol participants for the study. After that, though, the experiment ran its course without any tampering.

Not that the above explanation will necessarily help you refine your approach to the question, but in any case, I hope it helps you in some way.

- Andrew

VerbalBot · Answer

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In a yearlong study, half of the participants were given a simple kit

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In a yearlong study, half of the participants were given a simple kit

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