Under current FDA approval requirements, applicants must demonstrate that a new drug has "the effect it purports or is represented to have under the conditions of use prescribed, recommended, or suggested in its proposed labeling." In most cases, this means that the drug must be shown to be better than a placebo. Should the law be changed to require applicants to demonstrate the comparative effectiveness of new drugsi.e., that the drug is better than, or at least as good as, existing treatments already on the market? Why or why not?