Hardarson 2008.

Study characteristics
Methods	Study design: randomised controlled trial Duration and location of the trial: between November 2003 and February 2007 in Sweden Sample size calculation: a sample size with power calculation was performed 56 and 53 participants were randomised into the PGT‐A and control group, respectively.
Participants	Inclusion criteria: couples with infertility of female or male origin, intending to undergo IVF or ICSI, who had signed a written consent form and in which the age of the woman was ≥38 years were eligible for randomisation. The couple had to have at least 3 embryos of GQE, only 2 GQE were required if the participant only wanted 1 embryo back. Exclusion criteria: patients who had previously been randomised to either of the 2 study groups in this trial
Interventions	Type of biopsy: cleavage stage biopsy. Biopsy on embryos with at least 6 cells and less than 20% fragmentation. Mostly 1 blastomere removed. Genetic analysis: FISH analysis for chromosomes X, Y, 13, 18, 21
Outcomes	live birth rate Miscarriage rate Ongoing pregnancy rate Clinical pregnancy rate Proportion of women reaching embryo transfer Mean number of embryos per transfer
Notes	Treatment procedure: IVF or ICSI Embryo transfer policy: maximum 2 embryos for transfer
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Randomization into two groups was performed using a computerized randomization program"
Allocation concealment (selection bias)	Unclear risk	Judgement comment: concealment of allocation not stated
Blinding of participants and personnel (performance bias) All outcomes	High risk	Judgement comment: no blinding
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Judgement comment: non‐blinding not likely to affect objective outcomes
Incomplete outcome data (attrition bias) All outcomes	Low risk	Judgement comment: number of randomised participants is the number of analysed participants
Selective reporting (reporting bias)	Low risk	Judgement comment: no suggestion of selective reporting
Other bias	High risk	Judgement comment: high risk of within‐study bias due to the difference in day of embryo transfer between study arms (day 5 for intervention and day 3 for control) Funding: sponsored by the Swedish Medical Research Council and Serono Nordic AB