Table 1. General Characteristic of Studies.

Study (First author)	Country surveyed	Year of publication	Number of journal examined	Period studied	Number of advertisements	Number of distinct advertisements	Sampling method
Lexchin [24]	Canada	1999	5	1998	571	130	Convenience sample
Lankinen [17]	Finland	2004	4	2002	1036	245	Convenience sample
Carandang [10]	Australia	1994	4	1991 and 1992	Not reported	127	Convenience sample
Vlassov [31]	Russia	2001	5	1998	397	207	Convenience sample
Chirac [11]	French speaking African countries (West African and Maghreb)	1993	6	1990	1311	141	Convenience sample
Cooper [19]	The US	2005	10	1999	Not reported	438	Convenience sample