1. Department of Biostatistics and Epidemiology; University of Pennsylvania; Philadelphia PA U.S.A.
2. Fred Hutchinson Cancer Research Center; Seattle WA U.S.A.
3. Department of Internal Medicine; University of Utah; Salt Lake City UT U.S.A.
4. Department of Biostatistics; University of Washington; Seattle WA U.S.A.
5. McDonough School of Business; Georgetown University; Washington, DC U.S.A.