First, consistent cross-country data did not exist regarding questionnaire content, sampling methodology, and data analysis. This was true for adults and adolescents. Many individual countries (especially developed countries) had good surveillance systems in place for adult data (see Tobacco Control Country Profiles, volumes I and II), some countries had systems in place for data on adolescents (for example, Australia, Canada, Thailand, and the United States), but only a very few cross-country systems were in place and most of these were in Western Europe (for example, Health Behaviour in School Aged Children [HBSC] and the European School Survey Project on Alcohol and Drugs [ESPAD]).