Farren 2017.

Study characteristics
Methods	Study type: single‐centre, parallel RCT
Participants	240 pregnant women from Ireland Inclusion criteria: women were 10 to 16 weeks' gestation at trial entry. Pregnant women with a family history in a first‐degree relative of diabetes, either type 1 or type 2, were eligible for inclusion.  Exclusion criteria:  age younger than 18 years, multiple pregnancies, limited comprehension of English, and any pre‐existing liver or kidney disease or diabetes.  Timeframe: January 2014 to January 2016
Interventions	Intervention: combination of myo‐inositol 1,100mg, C‐chiro‐inositol 27.6mg, and 400 microgram folic acid daily  (N = 120) Duration of myo‐inositol supplementation; not stated Comparison: 400 microgram folic acid daily (N = 120)
Outcomes	Maternal: occurrence of gestational diabetes, gestational hypertension, induction of labour, the mode of delivery, perineal trauma Criteria used to diagnose GDM: IADPSG Infant: birth weight, shoulder dystocia, brachial plexus palsy, neonatal intensive care unit (NICU) admission, neonatal hypoglycaemia, respiratory distress syndrome Further information was received following email contact with the authors.
Notes	Sample size calculation: yes Intention‐to‐treat analysis: yes  Induction of labour was not reported in the study. Funding source: supported by the Coombe Women & Infants University Hospital. The food supplement was provided at no cost from Lo.Li. Pharma. Conflicts of interest: none reported Ethical approval was granted by the Hospital Research Ethics Committee in June 2013. The trial was registered with the ISRCTN registry and assigned the trial number ISRCTN92466608.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was carried out by an independent statistician.
Allocation concealment (selection bias)	Low risk	The author confirmed that they used sealed opaque and sequentially numbered envelopes.
Blinding of participants and personnel (performance bias) All outcomes	High risk	The Investigators knew which supplement was dispensed and the women knew which supplement they were taking, but the clinicians managing the pregnancy and delivery were blinded.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Trial was open label, investigators were aware of which supplement was dispensed.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The authors provide a list of the flow of participants through their trial.
Selective reporting (reporting bias)	Low risk	All collected outcomes have been reported.
Other bias	Low risk	Authors had no potential conflicts of interest related to the article.