Logical Reasoning

PT121 · S4 · Q19 Fifty chronic insomniacs participated in

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Fifty chronic insomniacs participated in a one-month study conducted at an institute for sleep disorders.

Given that ...

One group got a placebo and one group got a new drug.

Why is it that ...

For both groups, 80% reported insomnia relief during first two weeks, 90% of those who had relief said that insomnia came back by the third week.

Evaluate

Since the placebo group and the experimental group (the one receiving the drug) are essentially experiencing the same results, it makes it seem like the drug does nothing.

The whole point of administering a placebo to a control group is to figure out what effects are from the drug and what effects are from the placebo.

So it looks like the drug does nothing significant for insomnia, but the placebo effect (the effect of thinking you're receiving a treatment that should be helping) provides some short-term relief that wears off.

Goal

It's possible the correct answer will use a different storyline to explain the data, but we basically want to know 1) why is the placebo group seeming to get as much relief as the group that got the drug?

2) why are the people who got relief back to normal by the third week?

19.

Which one of the following, if true, most helps to explain all the data from the study?

Because it is easy to
Half Explains
When it comes to our two pieces of data, 1) why is the placebo group seeming to get as much relief as the group that got the drug? 2) why are the people who got relief back to normal by the third week? this answer seems to explain #2 -- most people will lose the relief they got from the drug by the third week. But it doesn't explain #1 -- why did the placebo group have the same level of symptom relief during the first two weeks as the drug group did?
15% picked this
The psychological comfort afforded by
Half Explains
When it comes to our two pieces of data, 1) why is the placebo group seeming to get as much relief as the group that got the drug? 2) why are the people who got relief back to normal by the third week? this answer seems to explain #1 — most people will get relief from their insomnia by the psychological comfort (i.e. the placebo effect) of just believing they've taken something for their insomnia. Thus, even if the drug does nothing, the placebo group and the drug group will both experience relief. But it does nothing to explain the second piece of data, which is why the relief fades after a couple weeks.
8% picked this
The new drug is very
Half Explains
When it comes to our two pieces of data, 1) why is the placebo group seeming to get as much relief as the group that got the drug? 2) why are the people who got relief back to normal by the third week? this answer seems to explain #1 — the placebo group got as much relief as the drug group because the drug isn't actually effective; thus, the relief that everyone is getting is just psychologically induced placebo effect But it wouldn't explain #2, why the effect fades after a couple weeks.
2% picked this
Correct
Most insomniacs sleep better in
Why this is right
When it comes to our two pieces of data, 1) why is the placebo group seeming to get as much relief as the group that got the drug? 2) why are the people who got relief back to normal by the third week? this explains both. #1 - the drug has no effect, so the placebo group and the drug group have matching experiences because neither the placebo nor the drug is doing anything chemically for them. Meanwhile, most of them are getting some relief from insomnia (the inability to fall asleep) simply by sleeping at this research institute. The new surroundings shake them out of their insomnia rut and allow them to fall asleep (so 80% of them report significant relief from their sleeplessness). #2 - the insomnia comes back by week three for all the people who experienced relief because at that point the institute's sleeping accommodations are no longer a "new environment". The novelty has worn off, the subjects' bodies are now accustomed to falling asleep at the institute, and so they're back to experiencing insomnia as though they were at home (or in any other familiar environment).
Skill tested: Paradox · how this choice captures the argument's function is the move to repeat next time.
73% picked this
Some insomniacs cannot reliably determine
Explains Neither Too Weak: some
The only way this answer would have anything to do with explaining either piece of data is if we tried to weave a story that "insomniacs have no idea how much sleep they are or aren't getting, so the 80% and 90% figures from the study are totally detached from reality". However, the word "some" just means at least one, so we can't go from "there is at least one insomniac who can't reliably tell how much sleep they've gotten" to "80% of people from both groups reported similar relief because an identical percentage of each group was just confused about whether things had improved or not. Similarly, 90% of the group who thought they were sleeping more randomly switched to thinking they had reverted back to previous sleeping levels in the third week since they don't really have a good feel one way or the other."
3% picked this

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