Logical ReasoningDifficulty: Hard

PT11 S4 Q19 Explanation

The proposal to extend clinical trials

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsFlaw

Keep going in LSAT Lab

  • Save & drill this skill build targeted practice sets from questions like this one

  • Video walkthroughs watch every question solved step by step

  • 81 official LSATs as questions, timed sections & full-length tests

Full official LSAT questions are available through LawHub. This page provides LSAT Lab's explanation, strategy, and review tools without republishing the full official question.

Stimulus

The proposal to extend clinical trials, which are routinely used as systematic tests of pharmaceutical innovations, to new surgical procedures should not be implemented. The point is that surgical procedures differ in one important respect from medicinal drugs: a correctly prescribed drug depends for its effectiveness only on the drug’s composition, whereas transparently related to the skills of the surgeon who uses it.

What this question is testing

Flaw

Conclusion

The author wants to block clinical trials for new surgical procedures.

Evidence

The reason: surgery effectiveness depends on the surgeon. Drug effectiveness doesn't — it's all about the chemistry.

Evaluate

The author treats clinical trials as if they only measure effectiveness. But trials do more than that. They also detect harm — whether a procedure is intrinsically dangerous or worse than existing options.

And the surgeon-skill issue doesn't cancel out harm detection. Even with skill variation, if a procedure is fundamentally bad, a trial can show it. So the author's reason against trials doesn't actually rule out one important reason for them.

Goal

Find the answer that calls out this overlooked use of trials — detecting intrinsic harm.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
19.

The reasoning in the argument is flawed because

Answer choices

  1. Correct42% picked this

    does not consider that new surgical procedures might be found to be intrinsically more harmful than the

    Why this is right

    This nails the gap. The author's argument focuses entirely on whether trials can measure surgical effectiveness. But trials also reveal whether a new procedure is intrinsically more harmful than the best existing alternative — and that's a critical safety reason to run trials, regardless of surgeon-skill variation. The author hasn't considered this purpose, so the argument against trials is incomplete.

    Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.

  2. Bad Objection10% picked this

    ignores the possibility that the challenged proposal is deliberately crude in a way designed to elicit criticism to be

    This complains that the proposal might be deliberately crude to invite refinement. Even if true, that wouldn't weaken the author's argument — it's a meta-claim about the proposal's design, not about whether the author's reasoning supports rejecting it. A real flaw answer should expose a defect in the author's logic.

  3. Bad Assumption19% picked this

    assumes that a surgeon’s skills remain unchanged throughout the surgeon’s

    This says the argument assumes surgeon skills don't change over a career. The argument doesn't need that assumption — the argument just needs surgeon-skill variation to exist (which it does, even within a single career). Skill changing over time doesn't undermine the author's premise that effectiveness depends on skill.

  4. Bad Description19% picked this

    describes a dissimilarity without citing any scientific evidence for the existence

    This says the argument describes a dissimilarity without scientific evidence. But "drug effectiveness depends on composition; surgery effectiveness depends on surgeon skill" is a reasonable observation that doesn't require scientific citations to be plausible. The flaw isn't lack of citations — it's the overlooked alternative purpose of trials.

  5. Bad Description9% picked this

    rejects a proposal presumably advanced in good faith without acknowledging any

    This says the author rejects a proposal without acknowledging good faith. That's a tone-policing complaint, not a logical flaw in the argument. Failing to credit the proposers' intentions doesn't make the reasoning flawed; the actual flaw is overlooking harm-detection as a purpose for trials.

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free