Self-study
Conclusion The proposal to extend clinical trials, which are routinely used as systematic tests of pharmaceutical innovations, to new surgical procedures should not be implemented. ███ █████ ██ ████ ████████ ██████████ ██████ ██ ███ █████████ ███████ ████ █████████ ██████ █ █████████ ██████████ ████ ███████ ███ ███ █████████████ ████ ██ ███ ████████ ████████████ ███████ ███ █████████████ ██ ████ ███ ████ ███████████ ████████ █████████ ██ █████████████ ███████ ██ ███ ██████ ██ ███ ███████ ███ ████ ███
Argument Structure
The stimulus leads with its main point: a proposal that suggests using clinical trials, which are already used to test new pharmaceutical drugs, to test new surgical procedures, "should not be implemented." The next sentence provides the premise for this conclusion: the effectiveness of a correctly prescribed drug depends only on its composition, whereas a given surgical procedure can vary in effectiveness depending on the skills of the surgeon performing it.
Notable Assumptions
It might seem like the author makes a valid point. In theory, it might be easier to test a drug in a standardized way, since drugs can be mass-produced with the same composition, whereas a given surgical procedure might vary in effectiveness depending on different surgeons' skill levels.
The problem, though, is that the author goes from stating that the effectiveness of a surgical procedure is related to the surgeon's skill level to concluding that clinical tests should not be applied to surgical procedures: a value judgment that implies clinical tests will not be beneficial or useful in revealing the effectiveness of new procedures.
This doesn't have to be true: a surgeon's skill level is not the only factor determining the effectiveness of a procedure. Some procedures might simply be better or worse for a given outcome, regardless of the skill level of the surgeon conducting them. Imagine a procedure that is surprisingly simple and targeted at a specific, common ailment. Even if there is some variation based on how different surgeons carry out the procedure, clinical trials could still reveal that the procedure is more effective overall, regardless of a surgeon's skill level, than other procedures.
So a significant flaw in the argument is that the author identifies one factor that might cause a procedure to be more or less effective in a specific case — and then seemingly concludes that this factor rules out knowing whether that procedure is more or less effective overall than other procedures. This is like saying that because an athlete might run faster or slower based on their mood and the weather, it doesn't make sense to test whether they run faster or slower than other athletes.
19.
The reasoning in the argument ██ ██████ ███████ ███ ████████
a
does not consider ████ ███ ████████ ██████████ █████ ██ █████ ██ ██ █████████████ ████ ███████ ████ ███ ████ █████████ ██████████ █████████
Correct. This is a flaw in the argument: the author does not consider that, even though the effectiveness of any procedure in one particular case might vary based on the surgeon's skill, some procedures might be inherently more or less effective than others, regardless of the skill of the surgeon who performs them.
This answer choice effectively points out this flaw. If a new procedure is intrinsically more harmful than the treatments currently available, we would expect to see that it is generally less effective across the board, regardless of the surgeon performing it. Thus, clinical trials could reveal something very important about that procedure before it is adopted for general use.
b
ignores the possibility ████ ███ ██████████ ████████ ██ ████████████ █████ ██ █ ███ ████████ ██ ██████ █████████ ██ ██ ████ ██ ████████ ███ ████████
Nothing in the stimulus suggests that the proposal is "deliberately crude" so as to elicit constructive criticism. We would need more context and information even to determine that this is a possibility worth considering. From the stimulus as it stands, we have no reason to think it is, so it's not a flaw for the author to overlook this.
Also, notice that even if it were true that the proposal were designed this way, that doesn't necessarily counter the author's argument that the proposal shouldn't be adopted. Given that the author's premise is aimed at the fundamental structure of the proposal — the difference between drugs and surgical procedures means the same methods can't apply to both — it's not clear how the proposal could be "refined" in such a way that the author wouldn't reject it.
c
assumes that a ███████████ ██████ ██████ █████████ ██████████ ███ ███████████ ████████████ ████
This might be a tempting answer choice, because it does focus on a part of the stimulus connected to the argument's flawed logic: the point about the effectiveness of a procedure being linked to a surgeon's skills. But nothing in the argument suggests that the author assumes surgeons' skills remain unchanged throughout their careers. The author never says that a surgeon's skill level never changes.
In fact, this answer choice, if anything, strengthens the author's claim, which is about the variability in the effectiveness of a surgical procedure applied in any given case. The author's point is that the effectiveness of a surgical procedure will vary on a case-by-case basis, depending on the skill of the surgeons involved. This answer choice brings up another reason for the effectiveness of a procedure to vary even with the same surgeon, since a surgeon's skill level will change throughout their career. This just reinforces the author's point.
d
describes a dissimilarity ███████ ██████ ███ ██████████ ████████ ███ ███ █████████ ██ ████ █████████████
It's true that the author doesn't cite any scientific evidence for the dissimilarity he mentions — for instance, scientific papers establishing that drugs' effectiveness depends primarily on composition, while surgical procedures vary based on surgeons' skill levels.
But just because this answer choice accurately describes a trait of the stimulus doesn't mean that trait is a flaw. This dissimilarity is offered as a premise, and remember that on the LSAT, we usually give the premises the benefit of the doubt. Unless the stimulus gives us a reason to doubt the accuracy of the premises or the expertise of the author, it's usually safe to assume both — otherwise we would need footnotes for every LSAT stimulus.
So this answer choice would be a flaw if, for instance, the stimulus mentioned specific scientific evidence in favor of the proposal, and the author brushed that aside just based on feelings or vague assertions. That doesn't happen here: the premise is presented as fact, with no reason in the stimulus to doubt that fact. So it's not a flaw that there isn't additional evidence cited.
e
rejects a proposal ██████████ ████████ ██ ████ █████ ███████ █████████████ ███ ████ ████ █████
Irrelevant. We can assume the proposal was, as this answer choice says, "presumably advanced in good faith." But engaging with a good-faith argument doesn't require you to explicitly "acknowledge" that good faith, as if the author needed a clause somewhere in this stimulus saying, "And this proposal was offered in good faith."
You can acknowledge a good-faith argument by engaging with it seriously and offering relevant criticisms, which is — as far as the stimulus shows — what the author attempts to do. The premise he brings up might not entirely justify his conclusion, but it certainly is a relevant point. To go any further and draw conclusions about the motives of either the people making the proposal or the author of this stimulus would be to bring in external assumptions.