Supported by a research grant from the Robert Wood Johnson Foundation .

Disclosure forms provided by the authors are available with the full text of this letter at NEJM.org.

Drs. Sommers and Epstein previously served in the Office of the Assistant Secretary for Planning and Evaluation at the Department of Health and Human Services, but the views in this letter are those of the authors and do not represent those of the Department of Health and Human Services or the Robert Wood Johnson Foundation.