Salehpour 2009

Methods	Randomised, controlled, double‐blind trial
Participants	Women with PCOS attending IVF clinic (n = 46); Mean age Treatment group: 27; Control group 28 Exclusion criteria: infertility factors apart from anovulation, other pathologies, hormone consumption for less than 2 months before enrolment.
Interventions	1. NAC 200 mg: 1 tablet 3 times a day (n = 23) 2. Placebo (n = 23) 7 women lost to follow‐up. Reasons described were intolerance to the smell of medications and blood samples inappropriate for the study Treatment 6 weeks' duration Follow‐up 6 weeks
Outcomes	Ovulation Weight Endocrine Metabolic and hormonal factors
Notes	Trial carried out in Teheran, Iran, from February 2007 and February 2008 Informed consent. Power calculation. Ethics approved. Funding source stated, "research is supported by Shahid Beheshti Medical University"
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"In order to minimise the effects of confounding factors through a randomised method". Method not stated
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding (performance bias and detection bias) All outcomes	Low risk	"Medication was provided to patients by a midwife. Both patient and physician were blinded to the type of treatment regimen".
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	14 dropouts; 7 from each arm, reasons generally described but not for each woman
Selective reporting (reporting bias)	Low risk	All outcomes described in the text were reported
Other bias	Low risk	No other bias found