A medical researcher is working on a new treatment for a certain type of cancer. The average survival time after diagnosis on the standard treatment is two years. In an early trial, she tries the new treatment on three subjects who have an average survival time after diagnosis of four years. Although the survival time has doubled, the results are not statistically significant even at the 0.10 significance level. The most likely explanation is
A) the placebo effect is present, which limits statistical significance.
B) the sample size is small.
C) that although the survival time has doubled, in reality the actual increase is really two years.
D) the calculation was in error. The researchers forgot to include the sample size.

Question

Quizplus · Accepted Answer

The most likely explanation for the lack of statistical significance is that the sample size is small. With only three subjects in the trial, it is difficult to draw strong conclusions about the effectiveness of the new treatment. A larger sample size would provide more accurate data and increase the chances of finding statistically significant results.

A Medical Researcher Is Working on a New Treatment for a Certain