Countries in each WHO region were ranked, from
highest to lowest, by estimated number of smokers. The
first six countries in the European Region, as well as the
first five countries in each of other WHO regions were selected to give a sample with the highest contribution
to the global burden of smoking across all WHO regions.
In instances where country laws were not available,
or where verified translations were not accessible
electronically, the next country on the list was selected,
provided the numbers of smokers in both countries were
comparable. In the African and Eastern Mediterranean
regions, where these numbers were far apart, fewer countries
were selected. This led to a final selection of 25 countries:
six countries in the European region, five countries
in the Americas, South-East Asia and Western Pacific
regions, and two countries in the African and Eastern
Mediterranean regions.