In a clinical trial evaluating a new antihypertensive medication, researchers randomly assign 1,000 patients to either drug or placebo. At baseline, the drug group has a mean systolic BP of 158 mmHg and the placebo group has a mean of 156 mmHg. This difference is statistically significant (p = 0.03) but both groups were randomly assigned. Which of the following best explains this finding?
- A)Confounding by socioeconomic status
- B)Selection bias in patient enrollment
- C)The drug causes an increase in baseline blood pressure
- D)The randomization process failed
- E)Baseline imbalance due to random chance despite successful randomizationGABARITO
Explicação
With random assignment, baseline imbalances can occur by chance alone, especially with multiple variables being measured. The small difference of 2 mmHg with p=0.03 is statistically significant due to the large sample size (1,000 patients) giving high power to... Ver explicação completa e trilha adaptativa →