1. Yale University School of Medicine 333 Cedar St 06510 New Haven CT USA
2. Faculty of Medicine Mbarara University of Science and Technology P.O Box 1410 Mbarara Uganda
3. Makerere University College of Health Sciences P.O Box 7072 Kampala Uganda
4. Department of Surgery Loyola University Stritch School of Medicine 2160 S 1st Ave. 60153 Maywood IL USA
5. Department of Surgery University of California San Francisco School of Medicine 533 Parnassus Ave. 94143 San Francisco CA USA
6. Department of Social and Behavioral Sciences, Department of Epidemiology New York University School of Global Public Health 726, Broadway 10012 New York NY USA