[1] WAKE FOREST UNIV, BOWMAN GRAY SCH MED, DEPT PUBL HLTH SCI, WINSTON SALEM, NC 27103 USA
[2] UNIV WASHINGTON, DEPT MED, SEATTLE, WA 98195 USA
[3] UNIV WASHINGTON, DEPT EPIDEMIOL, SEATTLE, WA 98195 USA
[4] UNIV WASHINGTON, DEPT HLTH SERV, SEATTLE, WA 98195 USA
[5] UNIV ALBERTA, DEPT MED, EDMONTON T6G 2E1, ALBERTA, CANADA
[6] JOHNS HOPKINS UNIV, DEPT MED, BALTIMORE, MD 21218 USA
[7] JOHNS HOPKINS UNIV, DEPT EPIDEMIOL, BALTIMORE, MD 21218 USA
[8] UNIV NEVADA, RENO, NV 89557 USA
[9] UNIV VERMONT, DEPT PATHOL, BURLINGTON, VT 05405 USA
[10] UNIV CALIF IRVINE, DEPT MED, IRVINE, CA 92717 USA
[11] GEISINGER MED CTR, DEPT RADIOL, DANVILLE, PA 17822 USA