Caserta 2011.

Methods	Prospective, randomized, controlled, open, multicentric, group comparative clinical trial. Randomisation method: randomly assigned by sealed envelopes. Power analysis: not stated. Study period: from 2005 to April 2010. Sample size: 999 women. Conflict of interests: no.
Participants	Women with an indication for IVF or ICSI. Age: ≤ 40 years. Basal FSH ≤ 12 mIU/Ml. Exclusion criteria: > 3 previous unsuccessful assisted reproduction technique attempts, previous poor response to gonadotropin stimulation defined as < 3 preovulatory follicle, history of OHSS, polycystic ovarian syndrome, abnormal uterine cavity as evaluated by ultrasonography, presence of clinically significant system disease. Baseline characteristics to compare: mean age, body mass index, duration of sterility, primary infertility.
Interventions	Luteal started pituitary downregulation with an GnRH agonist. Standard treatment: rFSH dose of 150 IU (Gonal F1, Serono, SP, Italy) from day 2. Experimental treatment: rFSH fixed‐dose (150 IU); at the 7th day of stimulation 75 IU of rLH were added and the dose of rFSH customised according to response.
Outcomes	Primary endpoint: not stated. Secondary endpoints: number of oocytes (met II), mean number of 2 PN eggs, mean number of developed embryos, number of embryos transferred, number of patients with b‐hCG positive, number of clinical pregnancies (not defined), number of clinical developed OHSS (not defined).
Notes	Funding: not stated
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method used in random sequence generation not reported, study stated that: 'The randomization process was conducted by drawing sealed envelopes.....'
Allocation concealment (selection bias)	Low risk	Allocation was concealed in sealed envelope.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Non‐blinding is not likely to affect the outcomes of interest as they are objectively assessed.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	This was an open trial but non‐blinding of outcome assessment is not likely to affect the outcomes of interest as they are objectively assessed.
Incomplete outcome data (attrition bias) All outcomes	High risk	Imbalance in the proportions of withdrawals/losses to follow‐up between the two treatment groups and analysis was not on the basis of ITT.
Selective reporting (reporting bias)	Unclear risk	Primary outcomes were not reported.
Other bias	Low risk	Baseline demographic characteristics were comparable between the two treatment groups.