TABLE 1.

Description of Explanatory Variables Used in the Analyses

Variable and its source	Original variable and formation of the variable used in the analyses	Values
Family SES, Statistics Finland	Occupation-based socioeconomic status of the respondent’s mother and father from the National Registries of Statistics Finland. The registry data on socioeconomic circumstances had been obtained from national censuses conducted every fifth year until 1995 and from on-line registry data on a yearly basis from 2000 onwards. Classification of Statistics Finland25	Both parents’ unknown=0 Both parents upper white-collar=1 Either one upper white-collar=2 Either one lower white-collar=3 Either one blue-collar=4
Daily use of tobacco, AHLS	Combining questions on tobacco experimentation and frequency of tobacco use	No=1 Yes=2
Monthly drunkenness, AHLS	Question on frequency of alcohol use and drunkenness	No=1 (abstinence or only occasional drinking) Yes=2 (drunk once or more often a month)
Frequency of physical activity, AHLS	Combining questions on frequency of participation in physical exercise in sports clubs and frequency of leisure time physical activity	Low=1 (once a week or less) Medium=2 (2–3 times a week or less) High=3 (4 or more times a week)
Self-reported chronic diseases and disabilities AHLS	Question on long-term disease or disability that disturbs your everyday life	No=1 Yes=2
Overweight AHLS	BMI calculated from self-reported height (cm) and weight (kg)	No=1 (normal weight) Yes=2 (high BMI according to Cole’s criteria)26

AHLS indicates Adolescent Health and Lifestyle Survey; BMI, body mass index; SES, socioeconomic status.