“…Other confounding factors at the individual-level were identified in similar studies and included to control regressions by relevant socioeconomic and demographic characteristics: (1) age (20-29, 30-39, 40-49), (2) type of residence (urban, rural), (3) level of education (no education, primary education, secondary education, higher education), (4) number of children, (5) marital status (married, living together) and (6) occupational status. 14,21 Finally, to control for characteristics at the country-level, the following variables used in previous studies were included: 15 GDP (at constant prices, 2010) as a proxy measure of market size, the human development index and the index of economic freedom.…”