Discussion of Migraine Paper

Strength: Design for control group and treatment group is rigorous. To insure the accuracy of tests, the study puts lots of efforts on choosing randomization sample set. Weakness: The choice of treatment is related to Chinese medicine, which put limitation of sample selection. So it is possible that sample is not representative enough.

Weakness: From my point of view, the statement "There was only one statistically significant difference between groups, the age mean. The patients in the sham acupuncture group were older than in the real acupuncture group (P = 0.024)." is a very strange statement. Why would we have uncertainty (a p-value) in the difference in means of what are essentially completely observed populations? (the populations being the groups we assigned)? Could you please discuss the motivation behind this?

Strength: It appears that they put thought into their sample size calculations. The use of the results of the unpublished paper indicates they probably had decent estimates. As was mentioned above, the power seems small, however.