1. Department of Pediatrics; School of Medicine; University of California; San Francisco California USA
2. Center for Research and Development of Education; University Medical Center Utrecht; Utrecht the Netherlands
3. Department of Medicine; School of Medicine; University of California; San Francisco California USA
4. Departments of Family and Community Medicine and Obstetrics and Gynecology; School of Medicine; University of California; Davis California USA
5. Department of Medicine; School of Medicine; Stanford University; Stanford California USA
6. Department of Family Medicine; Keck School of Medicine; University of Southern California; Los Angeles California USA