www.reproductive-health-journal.com

Table 2
Included studies and quality assessment
Study	Sponsorship	Intervention	Methods

			Randomization	Allocation concealment	Blinding	Intention to treat analysis

Affinito [18]	Pharmaceutical company	GSD vs NGM	unclear	unclear	not	unclear
Droegemüller [8]	No information	LNG vs NE	unclear	unclear	not	yes
Dunson [12]	Family Health International	NG vs NE	unclear	adequate	not	not
Endrikat [19]	Pharmaceutical company	GSD vs DSG	unclear	unclear	not	yes
Endrikat [20]	Pharmaceutical company	LNG vs NE	unclear	unclear	not	yes
Foidart [26]	Pharmaceutical company	DSG vs DRSP	unclear	unclear	not	unclear
GSD group [13]	Pharmaceutical company	GSD vs DSG	unclear	unclear	not	yes
Halbe [29]	Pharmaceutical company	GSD vs DSG	unclear	unclear	not	yes
Huber [10]	Pharmaceutical company	DSG vs DRSP	unclear	unclear	not	yes
Koetsawang [28]	Pharmaceutical company	GSD vs DSG	unclear	unclear	not	unclear
L. America [27]	Pharmaceutical company	GSD vs DSG	block randomisation	unclear	not	yes
Loudon [17]	No information	GSD vs LNG	unclear	unclear	double blind	unclear
Percival [23]	Pharmaceutical company	NG vs NE	random list	unclear	investigator blind	unclear
Rabe [14]	Pharmaceutical company	GSD vs LNG	unclear	unclear	not	yes
Ramos [22]	Pharmaceutical company and UNFPA	LNG vs NE	unclear	unclear	double blind	yes
Reiter [21]	Planned Parenthood Centers	NG vs NE	unclear	unclear	not	unclear
Rossmanith [9]	Pharmaceutical company	DSG vs NE	unclear	unclear	double blind	yes
Serfaty [16]	Pharmaceutical company	GSD vs DSG	block randomisation	unclear	not	unclear
Shoupe [15]	Pharmaceutical company	DSG vs NE	computer generated random number tables	adequate	double blind	unclear
Singh [24]	Pharmaceutical company	DSG vs NE	unclear	unclear	not	yes
Weber-Diehl [25]	Pharmaceutical company	GSD vs NE	unclear	unclear	not	unclear
Zichella [11]	Pharmaceutical company	GSD vs DSG	unclear	unclear	unclear	yes

Kulier et al. Reproductive Health 2004 1:1 doi:10.1186/1742-4755-1-1

Table 2