So 2010.

Methods	Randomised controlled trial of fertility patients undergoing frozen embryo transfer in Hong Kong
Participants	226 patients randomised to either real (n = 113) or placebo acupuncture (n=113). The median age at thawing was 36 (34 ‐ 38) and 36 (34 ‐ 39) years for real and placebo acupuncture respectively. The BMI, duration and cause of infertility and previous experience of acupuncture were also comparable between the two groups.
Interventions	Needle acupuncture according to TCM principles or placebo acupuncture with Streitberger's sham placebo needles. Intervention performed by a certified Chinese acupuncturist with a degree in Chinese Medicine and 3 years experience
Outcomes	Overall pregnancy rate, clinical pregnancy rate, ongoing pregnancy rate, live birth rate
Assisted conception protocols	Standard, long protocol GnRH down‐regulation and the follicle stimulating hormone (FSH) or human menopausal gonadotrophin (hMG)
Notes	More patients in placebo group correctly guessed their randomisation compared to the true acupuncture group
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	participants were randomized by a computer generated randomization list
Allocation concealment (selection bias)	Low risk	Sealed opaque envelopes from the list was used. ‘The sequence of randomization was concealed until interventions were assigned.’
Blinding (performance bias and detection bias) All outcomes	Low risk	‘patients, clinical staff involved in the care of patients and embryologist were blinded to the treatment group assigned’. The codes were only revealed after the completion of the entire study. Control group also had placebo needles.
Incomplete outcome data (attrition bias) All outcomes	Low risk	226 participants randomized. All completed the study.
Selective reporting (reporting bias)	Low risk	LBR available.
Other bias	Low risk	None known