DISCUSSION
ANEUPLOIDY
Our study suggests that the use of an educational video could help women make informed choices about aneuploidy screening. In previous studies, poor knowledge was often cited as a reason for uninformed choice.A systematic review of the literature regarding informed choice showed that women preferred to learn about NIPS from their clinician.We additionally found that the rate of informed choice in the control group of 53.6% was relatively low compared with a study performed in Netherlands where NIPS is also offered as a primary screening option, which reported up to 75% of women making informed choices in their population.When deliberation was included as a criterion for making an informed choice, the intervention did not appear to result in a higher proportion of women making informed choices. Previous studies, which had included deliberation as a criterion for informed decision‐making, reported that the lack of deliberation was the main reason for uninformed choices.The psychological effects of uninformed choice have been described, such as increased decisional conflict,A notable finding of this study was that women in the intervention group appeared more likely to choose NIPS, while women in the control group appeared more likely to choose FTS as a screening option. Such a finding highlights the potential influence that the pre‐test counselling has on eventual test choice, in line with concerns about routinisation of testing. The observed difference in test choice between the two arms may be attributable to the possibility that the difference in limitations of FTS and NIPS was better explained by the intervention than the clinician's counselling, resulting in participants in the control arm simply choosing the cheaper test option. Qualitative interviews with subjects regarding their decisions and which component of the counselling influenced their decision would be valuable. Additionally, a survey of healthcare providers on how confident they felt in explaining the characteristics, advantages and limitations of each test would prove useful in determining causality.The strength of our study is that it is a randomised controlled trial performed in a setting, which offers both FTS and NIPS as primary screening options. While a significant amount of research has been performed on interventions aimed at improving informed choice with regard to prenatal screening, few studies were performed in settings where NIPS is offered as a primary screening option.Although a randomised controlled trial, there are several limitations in this study. The first is that it lacks qualitative data. Structured interviews with participants would be helpful in tailoring the contents of the video to suit their information needs. Secondly, although participants in the intervention group had higher knowledge scores compared to controls after having received the intervention, the design of the study does not prove that the intervention improved knowledge scores from baseline. Randomisation of participants aimed to reduce the possibility of selection bias, but baseline knowledge scores were not measured to prove that this was not different between groups. Thirdly, comparison of the length of clinic consult times would have been useful in determining whether the intervention helped to reduce consult times with the clinician as demonstrated in a similar study regarding informed consent for hysterectomy.