LSAT (Law School Admission Test)Logical ReasoningHard
A medical researcher states: 'Our new drug, 'VitalityX,' has been shown to significantly reduce the symptoms of chronic fatigue in 75% of patients in our clinical trials. This demonstrates that VitalityX is a highly effective treatment for chronic fatigue syndrome.'
- AIt fails to mention the size of the clinical trials.
- BIt does not compare the effectiveness of VitalityX to a placebo or alternative treatments.
- CIt assumes that symptom reduction equates to a cure for chronic fatigue syndrome.
- DIt fails to specify the duration of the symptom reduction.
Show answer & explanationAnswer & explanation
Correct answer: B. It does not compare the effectiveness of VitalityX to a placebo or alternative treatments.
The argument concludes that VitalityX is 'highly effective' based on 75% symptom reduction. However, without a control group (e.g., placebo or existing treatment), it's impossible to determine if this reduction is due to the drug itself, the placebo effect, or natural remission. A treatment's effectiveness is typically measured *relative* to something else.
Why the other options are wrong
- A. Trial size is important for statistical significance, but even with a large trial, the absence of a control group would still render the conclusion about 'effectiveness' scientifically unsound relative to other options.
- C. The argument states 'reduce symptoms,' not 'cure.' While 'highly effective treatment' might imply a significant impact, the core flaw is the lack of comparative data, not an overstatement of 'cure'.
- D. While duration is important for overall assessment, the primary flaw in concluding 'highly effective' is the lack of a baseline comparison, not just the duration.
Missing Baseline/Control Group
A flaw in reasoning where a claim about effectiveness or change is made without comparing the observed results to a baseline, control group, or alternative conditions.
- Makes it impossible to determine if the measured effect is due to the intervention.
- Fails to account for placebo effect, natural remission, or other confounding variables.
- Essential for establishing true causality or effectiveness in experiments.
Memory trick: To claim effectiveness, a comparison you must make; without a baseline, your argument will break!