Table 1.

Overview of variables included in the analysis

Variable	Description	Values / Measures
Outcome variables
Tobacco use	Ever tried tobacco	1 – ever, 2 – never
Tobacco age of onset	Age when the first whole cigarette was smoked	Number of years
Alcohol use	Ever drunk alcohol	1 – ever, 2 – never
Alcohol age of onset	Age when alcohol was used for the first time	Number of years
Individual level predictor variables
Gender	Sex of respondent	0 – male, 1 – female
Age	Years categorized as 15 – 19 years and 20 – 24 years	1 – 15-19 years, 2 – 20-24 years
Education	Education of the respondent	0 – preschool, 1 - primary, 2 – secondary, 3 - higher
Marital Status	Marital status of the respondent	0 – formerly married/in union, 1 – currently married/in union, 2 – never married/in union
Household income	Household income quintile	1 – Poorest, 2 – Second, 3 – Middle, 4 - Fourth 5 - Richest
Residence	Type of residence	0 – rural, 1 - urban
Exposure to Mass media	Mean exposure to mass media	Measured as mean frequency of: reading newspaper or magazine, listening to the radio, watching TV and Internet usage in the past month
Country level predictor variables
GDPpc	Gross Domestic Product per capita
GNI	Gross National Income
HDI	Human Development Index
GINI	GINI coefficient of inequality