Research and Evaluation, Kaiser Permanente Southern California, Pasadena, California;
CDC COVID-19 Response Team;
HealthPartners Institute, Minneapolis, Minnesota;
Institute for Health Research, Kaiser Permanente Colorado, Denver, Colorado;
Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California, Oakland,
California;
Marshfield Clinic Research Institute, Marshfield, Wisconsin;
Center for Health Research, Kaiser Permanente Northwest, Portland, Oregon;
Immunization Safety Office, CDC.