1. Rand Corporation, Santa Monica, CA 9040, USA
2. Primary Care and Population Sciences, University of Southampton, Southampton SO16, UK
3. Military Medical Research Program, Samueli Institute, Corona del Mar, CA 92625, USA
4. Department of Planning, Policy, and Design, University of California, Irvine, CA 92617, USA
5. School of Health Sciences, University of Canterbury, Christchurch 8140, New Zealand
6. Department of Veterans Affairs, VA Center for Implementation Practice and Research Support, Sepulveda, Greater Los Angeles, CA 91343, USA