Fu 2000

Methods	Women 'randomly allocated' to 2 groups. Method of randomisation not reported
Participants	186 women attending an MCH hospital, Qinghai, China. Women had regular menstrual periods and attended the clinic within 72 h of a single act of unprotected intercourse
Interventions	Anordrin 7.5 mg, twice daily, 12 h apart, for 2 days vs Mife 50 mg
Outcomes	Observed number of pregnancies, side effects and changes in menstrual pattern
Notes	No mention of post‐randomisation exclusion and loss to follow‐up Observed pregnancy/expected pregnancy/total number of women: anordrin 3/8/90; Mife 1/5/96
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 of pregnancy rate was reported
Other bias	Low risk	None detected