Wu 2010

Methods	Women randomly allocated to 2 groups. Method of randomisation, double‐blind trial was reported
Participants	998 healthy women with regular menstrual cycles and negative urine pregnancy tests who were requesting emergency contraception up to 72 h after unprotected coitus to receive single‐dose gestrinone 10 mg or Mife 10 mg
Interventions	Gestrinone: 4 gestrinone 2.5 mg capsules, and 1 placebo tablet identical in appearance to Mife Mife: 1 Mife 10 mg tablet and 4 placebo capsules identical in appearance to gestrinone
Outcomes	Observed number of pregnancies, side effects and changes in menstrual pattern
Notes	Observed pregnancy/expected pregnancy/total number of women: gestrinone 12/37/498; Mife 9/38/498 Lost to follow‐up: 2/998 Side effects: Nausea: gestrinone 38/498; Mife 51/498 Vomiting: gestrinone 1/498; Mife 1/498 Diarrhoea: gestrinone 4/498; Mife 1/498 Fatigue: gestrinone 9/498; Mife 18/498 Dizziness: gestrinone 8/498; Mife 13/498
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"The randomization sequence was computer generated by WHO and stratified by clinic. Randomization was performed using randomized blocks so that the chance of being assigned to either to either treatment group was equal in each block."
Allocation concealment (selection bias)	Low risk	"All clinics received sets of opaque, sealed envelopes containing the randomly allocated emergency contraception treatment pack assigned to a given participant number. When a woman was assigned to a participant number, the envelope containing the emergency contraception tablets with the corresponding participant number was given to her."
Blinding (performance bias and detection bias) All outcomes	Low risk	"Each envelope contained one tablet and four capsules. Participants assigned to the gestrinone group received four 2.5 mg gestrinone capsules and one placebo tablet identical in appearance to mifepristone." "The clinicians, participants and investigators were blinded to the drug assignments. Double‐blinding was maintained until after the final analysis."
Incomplete outcome data (attrition bias) All outcomes	Low risk	"The final analysis excluded two women (one gestrinone group, one mifepristone group) who were lost to follow‐up; thus, 498 participants in each group were included in the final analysis."
Selective reporting (reporting bias)	Low risk	Planned outcomes of pregnancy rate, side effects and menstrual bleeding in protocol were reported
Other bias	Low risk	None detected