Gulekli 2004.

Methods	Randomised controlled trial 23 women were randomised into 2 groups (10,000 units hCG priming (N = 14) and 20,000 units hCG priming (N = 9))
Participants	All women had a clinical diagnosis of PCOS and were aged < 40 years. They had a minimum 2‐year history of infertility and had failed to conceive after at least six previous cycles of ovulation induction with clomiphene citrate or gonadotrophins, with or without Intrauterine insemination.
Interventions	10,000 units or 20,000 units hCG priming 36 hours prior to immature oocyte retrieval
Outcomes	Primary outcome: Oocyte maturation rate 24 and 48 hours after immature oocyte retrieval Secondary outcomes: Fertilisation and cleavage rates
Notes	Power calculations were performed. Author contacted and responded but original data no longer available.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Treatment allocated "according to a computerised randomised table".
Allocation concealment (selection bias)	Unclear risk	"The numbers were kept in sealed envelopes and only opened once the decision to progress to immature oocyte retrieval was made. The envelopes were stored and opened by an independent coordinator". However, it is unclear if envelopes were opaque.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No comment made on whether participants were blinded to the dose used.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"The clinician performing the immature oocyte retrieval and the embryologist in the laboratory were unaware of the dose used."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Withdrawal not reported.
Selective reporting (reporting bias)	Unclear risk	Study protocol not available to check whether outcomes were prespecified.
Other bias	Unclear risk	Insufficient information to detect other sources of bias.