1. Saint Louis University Center for Health Outcomes Research, St. Louis, MO;
2. Saint Louis University Center for Outcomes Research, Saint Louis, MO;
3. Saint Louis University School of Medicine, St. Louis, MO;
4. Saint Louis University School of Medicine, Saint Louis, MO;
5. Saint Louis University, St. Louis, MO;
6. Washington University School of Medicine in St. Louis, St. Louis, MO;