The Incidental Economist reports a study from JAMA Pediatrics in which 120 small kids with “nonspecific acute cough” were randomized between 1) treatment with agave nectar, 2) placebo and 3) no treament. Parents, who were blind to the difference between agave nectar and placebo, answered surveys about the severity of the children’s cough before and after treatment. On almost all measured outcomes, the researchers found improvements for both the treatment and placebo groups compared to the no treament group, but no difference between them. The powerful tool of the placebo effect should be kept in mind by parents.