Chen 2013

Methods	Women were randomly allocated to 2 groups. Method of randomisation not reported
Participants	100 women attending in an obs/gyn clinic, Guangdong, China. Women had regular menstrual periods and attended the clinic within 72 h of a single act of unprotected intercourse
Interventions	LNG 0.75 mg in 2 doses vs Mife 25 mg single dose
Outcomes	Observed number of pregnancies and changes in menstrual pattern
Notes	Observed pregnancy/total number of women: LNG 3/50; Mife 0/50 Post‐randomisation exclusion and loss to follow‐up not reported
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 and loss to follow‐up not reported
Selective reporting (reporting bias)	Low risk	Planned outcome of pregnancy rate was reported
Other bias	Low risk	None detected