Xie 1998

Methods	Women randomly allocated to 3 groups. Method of randomisation not reported
Participants	600 women attending an urban MCH Hospital in Fuzhou, China Excluded women attending after 72 h, irregular menstrual periods and who had had multiple acts of intercourse
Interventions	Mife 150 mg vs Mife 50 mg vs Mife 25 mg, all single dose
Outcomes	Observed number of pregnancies, side effects and changes in menstrual pattern
Notes	Post‐randomisation exclusion or loss to follow‐up not reported Observed pregnancy/expected pregnancy/total number of women: Mife 150 mg 5/17/200; Mife 50 mg 8/15/200; Mife 25 mg 5/15/200
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	Post‐randomisation exclusion or loss to follow‐up not reported
Selective reporting (reporting bias)	Low risk	Reported planned outcomes
Other bias	Low risk	None detected