Bu 2006

Methods	Women were randomly allocated to 2 groups. Method of randomisation not reported
Participants	100 women attending  Fulaerji District Hospital, Qiqihaer, Helongjiang, China. Women had regular menstrual periods and a single act of unprotected intercourse within 72 h of attending the clinic
Interventions	Mife 10 mg single‐dose orally vs LNG 0.75 mg, 2 doses, 12 h apart, orally
Outcomes	Observed number of pregnancies, side effects and changes in menstrual pattern
Notes	Observed pregnancy/total number of women: Mife 10 mg: 1/50;  LNG: 1/50 Side effects: Mife: nausea 2/50; dizziness 1/50; low abdominal pain 3/50; diarrhoea 2/50  LNG: nausea 3/50; dizziness 1/50; low abdominal pain 4/50; diarrhoea 1/50   Changes in menstrual pattern:  Early: Mife 4/49; LNG  9/49 Delay: Mife  9/49; LNG  5/49 Spotting: Mife 1/49; LNG 2/49
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	Any losses to follow‐up or exclusion were not reported
Selective reporting (reporting bias)	Low risk	Planned outcome of pregnancy rate was reported
Other bias	Low risk	None detected