The opinions expressed are solely those of the authors. No official endorsement by the Agency for Healthcare Research and Quality or the Department of Health and Human Services is intended or should be inferred. Drs. Pezzin and Spillman contributed to this project while working at the Agency for Healthcare Policy and Research.
Address correspondence to Dr. William D. Spector, 540 Gaither Road, Suite 5000, Rockville, MD 20850.