WeakenDiff: Easy
Logic Breakdown
Passage Summary: A doctor thinks magnets help back pain because people using them felt better than people who did nothing.
Conclusion: Magnetic fields are likely an effective treatment for certain types of back pain.
Reasoning: In a study, patients who had magnets applied to their backs reported significantly more pain relief than a control group that received no treatment at all.
Analysis: The physician's argument relies on a classic experimental flaw: the lack of a placebo control. Because the second group received 'no treatment' rather than a 'sham' magnet, the reported relief in the first group could simply be the result of the patients' expectations of healing. To weaken this argument, we should look for an answer that suggests the results were caused by the psychological effect of being treated rather than the magnets themselves. If the patients knew they were getting a 'special' treatment, their reports of pain reduction are highly suspect.
Conclusion: Magnetic fields are likely an effective treatment for certain types of back pain.
Reasoning: In a study, patients who had magnets applied to their backs reported significantly more pain relief than a control group that received no treatment at all.
Analysis: The physician's argument relies on a classic experimental flaw: the lack of a placebo control. Because the second group received 'no treatment' rather than a 'sham' magnet, the reported relief in the first group could simply be the result of the patients' expectations of healing. To weaken this argument, we should look for an answer that suggests the results were caused by the psychological effect of being treated rather than the magnets themselves. If the patients knew they were getting a 'special' treatment, their reports of pain reduction are highly suspect.
Passage Stimulus
Passage Redacted
Unlock Full Passage4.Which one of the following, if true, constitutes the logically strongest counter to the physician's argument?
Correct Answer
A
A directly supplies a plausible alternative cause: if just knowing one has received a treatment can reduce pain, the magnet group’s self-reported improvement could be placebo-driven, not due to magnetic fields. That undercuts the causal conclusion most strongly.
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