1. Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon.
2. Oregon Health & Science University, Portland, Oregon.
3. University of California at Irvine, Irvine, California.
4. Rush University, Chicago, Illinois.
5. University of Hawaii, Honolulu, Hawaii.
6. Deep South Center on Effectiveness at the Birmingham VA Medical Center and the University of Alabama at Birmingham, Birmingham, Alabama.
7. University of Wisconsin-Madison, Madison, Wisconsin.