1. Kim Thuy Nguyen is with the School of Medicine; Shuangge Ma is with the School of Public Health, Biostatistics; and Jennifer Prah Ruger is with the School of Public Health, Health Policy and Administration, Yale University, New Haven, CT. Oanh Thi Hai Khuat, Duc Cuong Pham, and Giang Thi Hong Khuat are with the Institute of Social Development Studies, Hanoi, Vietnam.