| Methods |
Randomised controlled parallel trial, participants and providers unable to be blinded, intention‐to‐treat analysis performed, numbers of and reasons for withdrawals and dropouts stated, clearly defined interventions applied with standardised protocols, overall duration of follow‐up 6 cycles. Computer‐generated randomisation schedule, administered by numbered masked and sealed envelopes |
| Participants |
181 women with unexplained or mild male factor infertility of at least 3 years' duration or male subfertility for ≥ 1 year, with no abnormality found during full infertility investigation, which included basal body temperature chart, late luteal phase endometrial biopsy, postcoital test, hysterosalpingogram, diagnostic laparoscopy and ≥ 2 semen analyses. Exclusion criteria included cycle disorders, untreated endometriosis (AFS grade 2 to 4), and bilateral occluded tubes. |
| Interventions |
IVF vs IUI and IVF vs intrauterine insemination plus ovarian stimulation (IUI + SO) |
| Outcomes |
LBR per woman/couple |
| Notes |
Power calculation mentioned
Number of dropouts before completion of treatment: IUI, 19 couples out of 86 randomly assigned; IUI + SO, 16 out of 85 randomly assigned; IVF, 39 out of 87 randomly assigned (figures include couples with unexplained subfertility and mild male factor subfertility) |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Randomisation was computer‐generated |
| Allocation concealment (selection bias) |
Low risk |
"numbered masked and sealed envelopes" |
| Blinding (performance bias and detection bias)
All outcomes |
Unclear risk |
This was not mentioned |
| Incomplete outcome data (attrition bias)
All outcomes |
Low risk |
172/181 (95%) randomly assigned women with idiopathic subfertility were included in the analysis |
| Selective reporting (reporting bias) |
Low risk |
Study reported primary and secondary treatment outcomes adequately including adverse outcomes |
| Other bias |
Low risk |
Pre‐study power calculation was performed, and no other potential bias was observed |
