Table 2.

 Quality assessment of included case-control studies on hormone replacement therapy that reported venous thromboembolism

Reference	Appropriate inclusion and exclusion criteria*	First episode of venous thromboembolism	Objective diagnostic procedure	Adequate assessment of menopausal status	Accurate assessment of hormone replacement therapy†	Adequate analysis and adjustment	Score (0-6)
Boston CDSP 1974w21	Yes	Yes	No	Yes	Yes	Yes	5
Daly 1996w1	Yes	Yes	No	Yes	Yes	Yes	5
Jick 1996w3	Yes	Yes	Yes	Yes	Yes	Yes	6
Perez-Gutthann 1997w5	Yes	Yes	No	Yes	Yes	Yes	5
Smith 2004w9	Yes	Yes	Yes	Yes	Yes	Yes	6
Douketis 2005w10	Yes	Yes	Yes	Yes	Yes	Yes	6
ESTHER 2007 w11	Yes	Yes	Yes	Yes	Yes	Yes	6

Yes=1; no=0.

*Applied equally to cases and controls.

†Including route of oestrogen administration.