Reynaldo is reviewing a study on the effectiveness of a new drug-free remedy for depression. in the study, a group of participants was given a natural supplement for a period of six weeks. they rated their mood both before and after treatment. two-thirds of the group reported a marked improvement after the trial. what change in this study would do the most to increase reynaldo's confidence that sound scientific practices were followed?

The correct answer to this question is "Including a control group that did not receive the supplement." This is the change in this study that would do the most to increase Reynaldo's confidence that sound scientific practices were followed. It would help them distinguish the effect of the drug and other factors which might have influenced the study. Thank you for posting your question. I hope that this answer helped you. Let me know if you need more help.