In a study of cold symptoms, every one of the study subjects with a cold was found to be improved two weeks after taking ginger pills. The study concluded that ginger pills cure colds. Does this conclusion seem reasonable? What other conclusion could be reached instead?

Question

In a study of cold symptoms, every one of the study subjects with a cold was found to be improved two weeks after taking ginger pills.  The study concluded that ginger pills cure colds.  Does this conclusion seem reasonable?  What other conclusion could be reached instead?

PsyDAG · Answer

Was there a control group taking placeboes? If they also improved in two weeks, it is probably a placebo effect.