Acupuncture and pregnancy A study sought to determine whether the ancient Chinese art of acupuncture could help infertile women become pregnant.41 One hundred sixty healthy women undergoing treatment with artificial insemination were recruited for the study. Half of the subjects were randomly assigned to receive acupuncture treatment $25$minutes before embryo transfer and again $25$

minutes after the transfer. The remaining $80$subjects were instructed to lie still for $25$minutes after the embryo transfer.

Results: In the acupuncture group, $34$women became pregnant. In the control group, $21$women became pregnant.

(a) Describe how the three principles of experimental design were addressed in this study.

(b) The difference in the percent of women who became pregnant in the two groups is statistically significant. Explain what this means to someone who

knows little statistics.

(c) Explain why the placebo effect prevents us from concluding that acupuncture caused the difference in pregnancy rates.

$160$women undergo artificial insemination. Half were given acupuncture treatment as per ancient Chinese study some time before the insemination and other half were asked to lie down without that.

$34$ women were pregnant from first group and$21$women from other.

The three principles of experimental design are as:

• Control effect of lurking variables as use minimum two groups for comparison.
• Randomly assign subjects to each group and replication.

Hence, there area two groups based on receiving acupuncture.

Control lurking variables are the group who received acupuncture and the other group not receiving acupuncture and still asked to lie. Also, subjects are randomly assigned. Hence, experiment has$160$subjects.

Determining weather Chinese art of acupuncture makes infertile women pregnant, the difference in results obtained are extreme and cannot be ignored. Thi extreme difference is statistically significant.

This is due to the fact that the women who did not receive acupuncture were aware of this. There should be a third group that receives fake acupuncture treatment in order to consider placebo effect.