Sahu 2018.

Study characteristics
Methods	Randomised controlled trial Location of the trial: quote: "Cuttack, India"Method of randomisation: quote: “random number table”Method of allocation concealment: not statedSource of funding: none
Participants	Inclusion criteria: Women diagnosed with PCOS according to the Rotterdam criteria Exclusion criteria: Current or previous use of oral contraceptives, glucocorticoids, antiandrogens, ovulation induction agents, antidiabetic and anti‐obesity drugs or other hormonal drugs. Medical or surgical treatment of PCOS during the previous 3 months Presence of other endocrinopathies; except treated hypothyroidism on stable replacement doses of thyroid hormone Pregnancy, breastfeeding or desire for pregnancy during study interval (6 months) Inability to understand the proposal of the study precluding effective informed consent Number of women randomised: 101 MET: 50 OCP: 51 Number of women analysed: 86 MET: 42 OCP: 44 Number of withdrawal and reasons: MET: 8/ 16% Discontinued drug: 2 / 4% Lost F/U: 5/ 10% Pregnancy: 1/ 2% OCP: 7/ 13.7% Discontinued drug: 2/ 3.9% Lost F/U: 5/ 9.8% Summary characteristics: PCOS, with menstrual irregularities, 18 and 35 years. Age (years): MET mean (+SD): 27 (5.2) OCP mean (+SD): 26.8 (4.2) BMI (kg/m2): MET mean (+SD): 25.7 (2.6) OCP mean (+SD): 25.6 (2.7)
Interventions	Treatment: MET 500 mg twice a day/day Control: OCP (Ethinyl Estradiol 35 mcg / Cyproterone acetate 2 mg) 21 days/ stop 7 days Duration: 6 months Co‐intervention(s): medroxyprogesterone acetate (5 mg/day) for 5 days was administered in order to induce vaginal bleeding. All the patients were instructed to perform moderate physical activity and maintain a low carbohydrate diet throughout the trial.
Outcomes	Primary outcomes: Hirsutism score Adverse events: severe (requiring stopping of medication) and minorSecondary outcomes: Menstrual cyclicity, initiation of menses or significant shortening of cycles BMI (kg/m2) Serum total testosterone (nmol/L) Fasting insulin (mIU/L) Fasting glucose (mmol/L) Fasting total cholesterol (mmol/L) Fasting HDL cholesterol (mmol/L) Fasting LDL cholesterol (mmol/L) Fasting triglycerides (mmol/L)
Subjective outcomes	(a) Clinical parameters 1. Hirsutism score
Objective outcomes	(a) Clinical parameters 1. Adverse events: severe (requiring stopping of medication) and minor 2. Menstrual cyclicity, initiation of menses or significant shortening of cycles 3. BMI (kg/m2) (b) Hormonal parameters 1. Serum total testosterone (nmol/L) (c) Metabolic parameters 1. Fasting insulin (mIU/L) 2. Fasting glucose (mmol/L) 3. Fasting total cholesterol (mmol/L) 4. Fasting HDL cholesterol (mmol/L) 5. Fasting LDL cholesterol (mmol/L) 6. Fasting triglycerides (mmol/L)
Notes	Authors contacted about: to have the publication references. Power calculation: unclear, a priori, on ovarian stromal PI. Fasting insulin and total testosterone expressed in wrong unit in the article but with appropriate unit in the protocol.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “random number table”.
Allocation concealment (selection bias)	Unclear risk	Method of allocation concealment not stated Insufficient information available to permit a judgement of “low risk” or “high risk”.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "open‐label"
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information available to permit a judgement of ‘low risk’ or ‘high risk’. Blinding not stated.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Quote: "Lost of follow up, discontinued drug" unclear reason of withdrawal. Insufficient reporting of attrition/exclusions to permit a judgement of 'low risk' or 'high risk'.
Selective reporting (reporting bias)	Low risk	The study protocol is available and it is clear that the published reports include all expected outcomes, including those that were prespecified.
Other bias	Low risk	The study appears to be free of other sources of bias.