Hammar 1998.

Methods	Randomised double‐blind controlled trial
Participants	437 women with menopausal symptoms, in good physical and mental health, ≥ 1 year since last menstrual bleeding, menopausal symptoms, intact uterus, body mass index (BMI) < 30 kg/m2. Mean age 55 years
Interventions	Tibolone 2.5 mg/d 17β‐Oestradiol 2 mg plus norethisterone acetate 1 mg (E2/NETA) Administered for 48 weeks
Outcomes	Vaginal bleeding (more than 1 sanitary napkin per day)/spotting (just 1 sanitary napkin per day), hot flushes (1 = none, 2 = light, 3 = moderate, 4 = severe, 5 = very severe), sweating, vaginal dryness, endometrial cancer, breast cancer, cerebrovascular events
Notes	Timing: June 1992 to Feb 1995 Location: Denmark, Norway, Sweden Multi‐centre: 44 sites
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not specified
Allocation concealment (selection bias)	Low risk	Opaque sealed envelopes
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double dummy
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Not specified, but given the nature of outcomes eventually assessed, their evaluation is likely to be "objective"
Incomplete outcome data (attrition bias) All outcomes	Low risk	14/437 participants not assessed for lack of post‐baseline assessment
Selective reporting (reporting bias)	Unclear risk	Study protocol not available
Conflict of interest	High risk	Financed by drug manufacturer. Study authors have conflicts of interest