LSAT (Law School Admission Test)Logical ReasoningMedium

A medical researcher states: 'Our new drug, 'NeuroBoost,' has been shown to significantly improve memory function in elderly patients. In our trial, 70% of patients receiving NeuroBoost reported noticeable improvements, while only 30% of patients receiving a placebo reported similar improvements.'

  1. AMemory function can be influenced by various factors, including diet and exercise.
  2. BThe patients were told whether they were receiving NeuroBoost or the placebo.
  3. CThe study did not measure the *degree* of memory improvement, only whether it was noticeable.
  4. DThe placebo group consisted of patients who were generally healthier than those in the NeuroBoost group.
Show answer & explanation

Correct answer: B. The patients were told whether they were receiving NeuroBoost or the placebo.

The conclusion relies on comparing patient-reported improvements between the drug and placebo groups. If patients knew which treatment they were receiving (Option A), their expectations could have influenced their reported improvements, creating a 'belief effect' (similar to the placebo effect, but for the actual drug group) that biases the results and undermines the reliability of the comparison.

Why the other options are wrong

  • A. While true, this is a general statement about memory and doesn't point to a specific flaw in *this* study's comparison of drug vs. placebo.
  • C. This points to a limitation in the *measurement* but doesn't invalidate the comparison of *reported noticeable improvements* between the two groups, assuming the study was otherwise sound.
  • D. This would likely *strengthen* the case for NeuroBoost, as it would mean NeuroBoost patients (who were less healthy) still reported more improvement.

Lack of Blinding (Experimental Flaw)

A flaw in experimental design where participants or researchers (or both) are aware of which treatment is being administered, potentially leading to biased results due to expectations.

  • Can result in a 'belief effect' or 'observer bias'.
  • Double-blinding (neither participant nor researcher knows) is preferred.
  • Undermines the validity of comparisons between treatment and control groups.

Memory trick: Experiments need care, or conclusions beware!

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