Polak de Fried 2013

Methods	Prospective, randomized, double‐blind placebo‐controlled trial
Participants	Infertile women undergoing IVF/ICSI, 34 women with ICSI cycles and 18 oocyte donation (n = 52)
Interventions	1. Vitamin D 100.000 IU: 1 tablet per month (n = 26) 2. Placebo (n = 26) Trial duration; 5 consecutive months
Outcomes	Endometrial thickness Number of oocytes retrieved Cancellation rate Number of embryos transferred Implantation rate Clinical pregnancy rate Live birth
Notes	Conducted in Argentina,study dates not reported conference abstract Funding source not reported Author email; ester_polak@cermed.com. Author contacted on the 20th November 2015 regarding risk of bias factors and live birth data. Author replied 14th December 2015 regarding dropouts, miscarriage, adverse effects and live birth. Trial not yet published as a full text
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Fifty two patients were computer randomized"
Allocation concealment (selection bias)	Unclear risk	Unknown
Blinding (performance bias and detection bias) All outcomes	Low risk	"Double blind" (placebo control)
Incomplete outcome data (attrition bias) All outcomes	Low risk	"no dropouts" email from author
Selective reporting (reporting bias)	Low risk	No known selective reporting
Other bias	Low risk	No other bias found