1. Department of Preventive Medicine
2. Clinical Research Unit, Kaiser Permanente Colorado, Denver, Colorado
3. Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California, Oakland, California
4. Center for Vaccine Research, Kaiser Permanente Southern California, Torrance, California
5. Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon
6. Group Health Cooperative, Group Health Center for Health Studies, Seattle, Washington
7. Department of Vaccine Research, HealthPartners Research Foundation, Minneapolis, Minnesota
8. Epidemiology Research Center, Marshfield Clinic Research Foundation, Marshfield, Wisconsin
9. Department of Ambulatory Care and Prevention, Harvard Pilgrim Health Care, Boston, Massachusetts
10. Division of HIV/AIDS Prevention
11. Immunization Safety Office, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia