Table 1

Sampling structure used in each country

City 1City 2
Order AOrder BOrder AOrder B
 18–24 years2 groups2 groups2 groups2 groups
 25–34 years2 groups2 groups2 groups2 groups
 18–24 years1 group1 group1 group1 group
 25–34 years1 group1 group1 group1 group
  • The two cities in each country were Dhaka and Chittagong in Bangladesh, Beijing and Fuzhou in China, Cairo and Menia in Egypt, Delhi and Kolkata in India, Jakarta and Yogyakarta in Indonesia, Mexico City and Monterrey in Mexico, Manila and Pampanga in the Philippines, Moscow and Kostroma in Russia, Istanbul and Adana in Turkey, and Ho Chi Minh City and Hanoi in Vietnam.