Han 1996

Methods	Women 'randomly allocated' to 3 groups. Method of randomisation not reported
Participants	300 healthy women in Beijing, China, with regular menstrual periods, aged 18‐48 years, with attended the clinic within 72 h of a single act of unprotected intercourse
Interventions	Mife 25 mg, orally, 2 doses, 12 h apart vs Mife 25 mg, orally, single dose, vs Mife 25 mg + anordrin 7.5 mg, single dose
Outcomes	Observed number of pregnancies, side effects and changes in menstrual pattern
Notes	Post‐randomisation exclusions or loss to follow‐up not reported Observed pregnancy/expected pregnancy/total number of women: Mife 25 mg twice 0/7/100; Mife 25 mg single dose 1/6/99; Mife + anordrin 1/7/101
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Mentioned randomisation but description not adequate
Allocation concealment (selection bias)	Unclear risk	Method of allocation concealment not mentioned
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not mentioned
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No mention of post‐randomisation exclusion and loss to follow‐up
Selective reporting (reporting bias)	Low risk	Planned outcome was reported
Other bias	Low risk	None detected