An experiment is conducted to test the effectiveness of a social work intervention.The experimental group improves more than does the control group,but the results are not statistically significant.This means that
A) the intervention was not effective.
B) the intervention was effective, but not at a significant level.
C) we cannot rule out sampling error in inferring about the effectiveness of the intervention.
D) the sample size was too large.

Question

Quizplus · Accepted Answer

The fact that the experimental group improved more than the control group indicates that the intervention may have been effective, but the lack of statistical significance means that we cannot rule out the possibility that the difference between the two groups is due to chance or sampling error. Therefore, we cannot confidently conclude that the intervention was effective.

An Experiment Is Conducted to Test the Effectiveness of a Social