Table 1.

 Quality assessment of included randomised controlled trials on hormone replacement therapy that reported venous thromboembolism

Reference	Randomisation stated	Double blinding	Dropout and withdrawals	Generation of random numbers	Allocation concealment	Score (0-5)
PEPI 1995w12	Yes	Yes	3.0% dropout, 3.0% withdrawal	Computer generated block	Active drug and placebo in identical forms	5
HERS 1998w13	Yes	Yes	0% dropout, 2.1% withdrawal	Computer generated	Active drug and placebo in identical forms	5
EVTET 2000w14	Yes	Yes	23.6% dropout, 23.6% withdrawal	Computer generated block	Active drug and placebo in identical forms	5
ERA 2000w15	Yes	Yes	14.0% dropout, 4.0% withdrawal	Permuted block	Each woman received two tablets (active and placebo or two placebo)	5
WEST 2001w16	Yes	Yes	0% dropout, 1.4% withdrawal	Computer generated block	?	4
ESPRIT 2002w17	Yes	Yes	Not available	Computer generated block	Active drug and placebo in identical forms	4
WHI I 2002w18	Yes	Yes	3.5% dropout	Permuted block	Active drug and placebo in identical forms	5
WHI II 2004w19	Yes	Yes	2.2% dropout, 3.0% withdrawal	Permuted block	Active drug and placebo in identical forms	5
WISDOM 2007w20	Yes	Yes	0.01% dropout, 13.2% withdrawal	Computer generated block	Active drug and placebo in identical forms	5

Appropriate=1; No information or not appropriate=0.