Table 4

Sample sizes module 2 by countries and study groups

Country	Partner institution	Data collection regions	Sample sizes
			Current ATS user		Former ATS user		Non ATS user	Total N countries
			A_1: Frequent	A_2: Non-frequent	B_1: Frequent	B_2: Non-frequent	C: exposed
Germany	ZIS	Border Region to Czech Republic /metropolitan region of Hamburg	100	100	100	100	100	500
UK	UNEW	Northern England	100	100	100	100	100	500
Poland	APS	Metropolitan region of Warsaw	100	100	100	100	100	500
Netherlands	RG	Amsterdam/the region of Eindhoven	50	50	50	50	50	250
Czech Republic	OGCR	Border region to Germany	50	50	50	50	50	250
Total N groups			400	400	400	400	400	2000