Research and analysis

Working towards an international consensus on core standards for screening information: executive summary

Published 28 March 2022

1. Purpose

The UK National Screening Committee (UK NSC) commissioned the National Institute for Health Research (NIHR) Applied Research Collaboration West Midlands (ARC WM) Public Health research theme to define an internationally agreed set of principles to apply to the development and provision of evidenced-based information for individuals invited for screening.

Information was defined in this study as including physical or electronic information (to aid decisions) provided to people invited to screening, and additional support (such as web-based decision aids or tailored information). It is intended that the final set of principles will help inform international consensus on informed choice in screening.

2. Introduction

The content and context of information provided to people who are invited to different health screening programmes can influence service uptake and subsequently their health and wellbeing. The provision of evidence-based screening information is essential in order to facilitate informed choice and to support an individual’s autonomy when making decisions about screening^{[footnote 1] [footnote 2]}.

This study focused on 2 screening conditions:

1. Breast cancer screening (mammography).
2. Fetal anomaly screening (for Down’s syndrome, Edward’s syndrome, and Patau’s syndrome).

The 2 screening conditions were selected as representative programmes, from which general principles could be developed. The study draws on examples of screening information from countries across Northern and Western Europe and selected English-speaking countries. Following discussions with PHE, the researchers compiled a list of countries that have organised population-based screening programmes. They restricted the number of countries and languages included to align with the time and resource constraints of this project.

2.1 Research aims and objectives

The primary aim of the study was to define a set of principles to apply to the development and provision of evidenced-based information for individuals invited for screening.

The secondary aim of the study was to establish core content for those invited for screening to improve informed choice and knowledge and to decrease decisional conflict.

To fulfil the research aims, the following 4 research objectives were established:

1. To evaluate the effectiveness of decision aids for breast cancer and fetal anomaly screening in supporting informed choice and knowledge and in decreasing decisional conflict.
2. To understand the organisation of information production and development across Northern and Western Europe and selected English-speaking countries
3. To identify and assess the quality of information (given to individuals in selected countries) on breast cancer screening and fetal anomaly screening in improve informed choice and knowledge and decrease decisional conflict.
4. To establish an international expert group representing the countries involved to review, discuss, and define a set of principles to apply to the development and provision of screening information to improve informed choice and knowledge and to decrease decisional conflict

3. Methods

Researchers used mixed methods research involving systematic rapid evidence synthesis, primary research, and a consensus principles workshop with international representation. The findings from these 3 work packages were synthesised in a data integration approach to develop an overall data matrix.

In the evidence review, researchers aimed to determine the effectiveness of decision aids to improve informed choice and knowledge and to decrease decisional conflict in breast cancer and fetal anomaly screening (decisional conflict is defined as personal uncertainty about which course of action to take when choice among competing options involves risk, regret, or challenge to personal life values) ^{[footnote 3]}.

In the primary research, they conducted a range of interviews and a documentary analysis of the screening information materials provided by each of the participating countries (for both conditions where possible). Qualitative interview data was collected and analysed. Screening information materials were assessed using the International Patients Decision Aids Standards (IPDAS) Screening materials quality checklist.

The final section included a consensus workshop with attendees from some of the participating countries. During the online workshop, researchers reviewed and discussed the initial study findings against core standards for screening information. Feedback from the workshop informed the final set of principles.

4. Work package 1: rapid review of evidence

The rapid review of evidence summarised the impact of decision aids relating to breast cancer and fetal anomaly screening on informed choice, knowledge and decisional conflict as evaluated using randomised controlled trials (RCTs). Various types of decision aids were evaluated, including leaflets, booklets, interactive web-based decision aids, videos and phone/in person counselling. Twenty-four studies were eligible for inclusion. Twelve studies reported on breast cancer screening information and 12 on fetal anomaly screening. Risk of bias assessment showed a low or unclear risk of bias for the majority of the 24 included studies. Fetal anomaly screening studies were more likely to have a higher or unclear risk of bias compared to the breast cancer screening studies.

4.1 Breast Cancer Screening

Six studies ^{[footnote 4] [footnote 7] [footnote 8] [footnote 9] [footnote 10] [footnote 11]} assessed informed choice; all but one reported a statistically significantly higher proportion of women making an informed choice among those in the intervention group compared to the control group. The difference was not statistically significant in one study ^{[footnote 9]}. Eleven of the 12 studies on breast cancer screening also reported significant improvements in knowledge among the intervention group. The only study which reported no significant difference was the study conducted in Germany which compared an old less informative leaflet to a new and more informative one ^{[footnote 12]}. However, authors highlighted that neither of the leaflets were evidence-based.

Of the seven studies which assessed decisional conflict for breast cancer screening interventions, 3 showed ^{[footnote 4] [footnote 10] [footnote 11]} that decisional conflict reduced in the intervention group while the remaining four showed that decisional conflict was unaffected ^{[footnote 7] [footnote 8] [footnote 13] [footnote 14]}. Screening uptake for breast cancer screening was not significantly affected by the interventions in 4 of the 6 studies which assessed this ^{[footnote 4] [footnote 8] [footnote 11] [footnote 13]}. However, in one study among older women (aged 75 to 89 years) lower screening uptake was reported in the group that received a decision aid ^{[footnote 14]}. Another study that evaluated 2 intervention groups reported lower mammography uptake among those who received tailored printed material (TP) compared to usual care, while those who received tailored printed material alongside tailored telephone counselling (TC) had higher uptake ^{[footnote 15]}.

4.2 Fetal Anomaly Screening

Two of the 4 studies that assessed informed choice reported that a significantly greater proportion of women in the intervention group made an informed choice ^{[footnote 16] [footnote 17]}. Bjorklund and others also showed that a higher proportion of women in the intervention group made an informed choice although the difference was not statistically significant ^{[footnote 18]}. In the fourth study, an interactive, web-based decision aid did not improve informed choice ^{[footnote 19]}. However, it is worth noting that the rate of informed choice was assessed as high at baseline (93%) and therefore challenging to improve. In addition, only 30% of those who were allocated to the intervention group accessed the website which may have contributed to the apparent lack of effect.

Nine of the 11 studies that assessed the effects of decision aids on knowledge relating to fetal anomaly screening reported improvement in knowledge among the intervention group ^{[footnote 16] [footnote 17] [footnote 18] [footnote 19] [footnote 20] [footnote 21] [footnote 22] [footnote 23] [footnote 24]}. The remaining 2 studies reported no significant difference between the intervention and control groups ^{[footnote 25] [footnote 26]}. Two of the 6 studies that assessed decisional conflict suggested that the interventions decreased decisional conflict ^{[footnote 22] [footnote 23]}. The remaining 4 studies showed no significant difference between intervention and control groups ^{[footnote 16] [footnote 17] [footnote 20] [footnote 27]}. In 7 studies, fetal anomaly screening uptake was not affected by the interventions ^{[footnote 17] [footnote 18] [footnote 21] [footnote 23] [footnote 24] [footnote 25] [footnote 26]} but in one of the studies invasive diagnostic testing was significantly lower in the intervention group compared to the control group ^{[footnote 20]}.

4.3 Key findings

For both breast cancer and fetal anomaly screening, the available evidence showed that informed choice and knowledge improved among those who received decision aid interventions (for example, online leaflet, printed leaflet, workbooks).

Decision aids improved informed choice and knowledge without raising decisional conflict.

Risk of bias (RoB) assessment suggested that the majority of included studies were at low or unclear RoB.

5. Work package 2: interviews and documentary analysis of screening information

5.1 Summary of interview findings

Researchers interviewed 14 participants from across the 8 countries included in the study. The majority were female and in senior roles in their organisations. Four main themes were identified during the qualitative analysis:

• development process
• content and purpose
• delivery of and access to screening information
• wider influences on information and screening

Fetal anomaly and breast cancer screening programmes had some common features. Input from users, members of the public and patient organisations was incorporated. Countries had written guidelines, or participants reported implicitly understood guidelines for how to develop information.

The ability to customise information regionally varied widely. There was no ability to customise or adapt in some countries, while in others, different regions adapted standard templates as needed. The majority of countries provided tiers of information, with a more basic level through the leaflet, and more complex information available online. Almost all participants stated that the purpose of their leaflet was informed choice, and most viewed accurate coverage of the benefits and harms (for example, earlier diagnosis, greater chance of survival, false negatives, overtreatment) of choosing to be screened or not as the most important information. All but one participant made comments suggesting that some effort was made in their leaflet to use clear and simple language. Length and legal requirements for and around the leaflet varied considerably. Time given to people to make a decision about the screening ranged from immediately after being given the information (on the spot) to a few weeks. Participants reported having some alternative provision for those with other languages, or for population groups with specific other needs.

5.2 Summary of documentary analysis findings

The information and materials provided to people invited for screening were assessed for all 8 countries. Researchers used the Picker institute IPDAS screening materials quality checklist to assess the quality of the information. Breast cancer screening material mainly included leaflets, although materials provided by Sweden only included webpages. For fetal anomaly screening, 4 countries provided a leaflet and 3 provided a webpage.

The information materials for both breast cancer screening and fetal anomaly screening varied widely in length. The majority of documents were in a paper leaflet format with fewer countries providing website information. Scores across IPDAS domains were intermediate (3 out of 5). The total IPDAS quality rating score for breast cancer was slightly higher compared to fetal anomaly (26 versus 23). The presentation, structural integrity and consistency of the breast cancer information was of higher quality in comparison to fetal anomaly screening information.

5.3 Key findings

Almost all participants stated that the purpose of their leaflet was informed choice, and most viewed accurate coverage of the benefits and harms (for example, less invasive treatment due to earlier diagnosis, prevention of death, false positives, overtreatment) of choosing to be screened or not as the most important information.

For both breast cancer and fetal anomaly screening, information was presented in a tiered format (starting with basic information and building it through).

Using an independent quality evaluation tool (IPDAS quality checklist), the quality of screening information across all countries was assessed as better for breast cancer screening than for fetal anomaly screening.

The presentation, structural integrity and consistency of the information provided was more robust for breast cancer information materials in contrast to fetal anomaly information material.

Information materials varied in length with an average of 6 to 9 pages. Researchers did not find a clear trend in the length and volume of materials.

The majority of countries stated that facilitating informed choice is the primary purpose of their information given to people who are invited to or undertake screening.

6. Work package 3: consensus principles workshop with international representation

In the workshop researchers aimed to capture the views of those who develop, provide, commission, or receive screening information. There were 27 attendees from 5 countries: England, The Netherlands, Scotland, Norway and Canada. The initial findings from the interviews and documentary analysis of screening information were reviewed and discussed with people from across the 5 countries.

Participants were asked to rank statements which were informed by interim findings and to provide free text data about each statement. These were typed on to the virtual whiteboard by the participants. Researchers recorded and transcribed the workshop. Statements derived from the workshop included that:

• screening information should be based on unbiased, up-to-date scientific evidence
• people should be fully informed of the benefits and harms screening using simple, clear language adapted for relevant minority groups where necessary
• numerical information including probabilities and statistics should be provided in an understandable way (for example through infographics), and that people invited for or attending screening should be helped by healthcare professionals to make the right decisions for them

Participants also agreed that users or lay people should be involved in the process of creating screening information and that there should be a clear, transparent systematic process for creating information. They considered that determining the quality of decision making is difficult and that inclusion of conflicts of interest statements in screening information was not realistic. Benefits and harms of screening and the screening process were universally reported as existing in information materials in the rapid review, interviews, actual materials assessed, and online consensus workshop.

7. Data integration and recommendation statements

Researchers integrated the findings from the 3 work packages, using a mixed methods matrix approach, where evidence from each source was compared and collated. Using this approach, they identified 24 recommendation statements which they structured across the following 4 domain categories:

• content and purpose of screening information
• development of screening information
• delivery of and access to screening information
• wider influences on information of screening

The statements reported below are ranked according to domain category and strength of consensus in the findings of work packages.

7.1 Strong consensus

Content and purpose of screening information recommendations:

1. Information should clearly highlight that screening is a personal choice.
2. Information should include a clear statement on the benefits and harms of screening, supplemented by visual aids (infographics). Benefits include prevention of death/greater chances of survival, less invasive treatment due to earlier diagnosis of disease, improved knowledge. Harms include overdiagnosis, anxiety, false positives or false negatives and overtreatment, and the consequences that flow from these.
3. Information should provide a clear statement on the estimates of probabilities of the condition and potential positive and negative outcomes from screening using either prevalence estimates, event rates, or survival rates.
4. Information should use easy to read and simple language supported by visual aids to help understanding.

Development of screening information recommendations:

1. Information should be provided using a tiered approach, starting with basic concepts then building up to more complex information.
2. Behavioural science support should be used to develop a decision making approach, for example, in the inclusion of interactive worksheets ^{[footnote 28]}.

Delivery of and access to screening information recommendations:

1. Screening information should be distributed digitally online (with interactive features) and/or in person (where possible) either by post, or at appointments. A hard copy should be available for people who are unable to access online material. Where possible, feedback should be obtained as to the acceptability of delivery mode.
2. Support tools (for example values clarification exercises ) to elicit personal values, priorities and discussions with healthcare professionals should be encouraged to support informed decision making.

7.2 Moderate consensus

Content and purpose of screening information recommendations

1. Information should be checked for updates regularly (may range from 3 to 5 years) and if new evidence is found updates should be made to information.
2. Information should address population subgroups such as different age groups, or those with different languages, and should be culturally appropriate.

Development of screening information recommendations

1. There should be a systematic and transparent process for developing information.
2. Accessible screening protocols should be informed by high quality up to date scientific evidence.

Delivery of and access to screening information recommendations:

1. A wide range of healthcare organisations and units, charities, and the government should be involved in the screening process.

Wider influences on information of screening recommendations

1. Equality, diversity, and inclusion in screening information should be ensured by generating tailored information such as publishing in different languages, addressing ethnic minorities, religious beliefs, and health literacy. Field testing of screening information should be undertaken with users.
2. Resource constraints exist in almost all countries (for example, cost of physical copies versus online information provision) and should be taken into account in decisions on the generation, information updates, and distribution of screening information.

7.3 Low consensus

Content and purpose of screening information recommendations:

1. The definition of screening should be stated along with the actual process and all tests involved.
2. Information should include practical information such as what to wear, how to reschedule appointments and how long the process should take.
3. Information should include a statement on general data protection regulations. Development of screening information recommendations
4. National programmes should help to provide customised information for regional programmes so that the content of tailored information provision can be standardised and quality assured.
5. Development of information should involve a public consultation process.

Delivery of and access to screening information recommendations

1. Sufficient time to decide on screening participation should be allowed and should be appropriate to the screening programme.
2. Prompting questions by healthcare professionals to support decision-making process should be provided where possible.
3. A scheduled appointment or dedicated meeting time between a healthcare professional and the person invited to screening should be offered to each person to provide them with the opportunity to discuss the decision being made.

Wider influences on information of screening recommendations

1. Conflicts of interest should be clearly declared in all information provided to people invited to screening.

8. Strengths and limitations

8.1 Strengths

One of the notable strengths of this study was the collaborative approach to setting the research aims and objectives between the research team and those who develop and deliver screening services.

Data was collected from 8 different countries in this study.

Contribution from members of the public was sought at the project planning phase and during the consensus workshop.

In the rapid review, the study selection was conducted independently by 2 reviewers, and checked for accuracy by a third reviewer to reduce the risk of selection bias.

Interview data was collected by trained researchers following a semi-structured interview guide to ensure consistency. Qualitative codes were initially reviewed independently by 2 researchers to inform a coding framework and ensure consistency of coding.

Information material assessment was conducted independently by 2 reviewers to reduce the risk of analysis and reporting bias.

The virtual consensus workshop included a range of topic experts, service providers, stakeholders, academics and service users form different countries. Each participant was provided with a random username to ensure anonymity of written responses.

A matrix approach was used to integrate qualitative and quantitative mixed methods data. Integration enabled researchers to compare findings across data sources to determine where a consensus in the findings of work packages existed.

8.2 Limitations

Due to limited time and resources, researchers did not conduct independent double data extraction and quality assessment in their rapid review. However, these were checked by second reviewers to ensure accuracy.

Only articles published in the English language were included which may have introduced language and publication bias.

During the workshop researchers were unable to achieve full representation from all countries who participated in the study. However, they had representation from The Netherlands, Norway, Scotland, Canada and England.

The integration matrix was informed by 3 work packages (published evidence, primary qualitative data and information material, and the consensus workshop). Limitations of each work package would potentially influence the final recommendations. However, the study recommendations are in line with previous evidence, principles and guidance.

9. Conclusions

The University of Warwick undertook this study in response to a need for a rapid and responsive mixed methods research project to develop a set of principles for the development and provision of evidenced-based information for individuals invited for screening. The set of principles will help inform international consensus towards informed choice in screening.

This study used both primary and secondary data collection methods to generate 24 recommendation statements for the facilitation of informed choice in screening information. These statements are summarised across 4 key domain categories (content and purpose of screening information, development of screening information, delivery of and access to screening information, wider influences of information of screening) and ranked according to the consensus across the different types of study data.

Researchers identified common issues and challenges faced by screening programmes and suggested recommendations for research.

9.1 Implication for policy and practice

Implications for screening policy and practice have emerged from this work. Researchers found that there are a number of decision support models in screening. However, how they work in practice is not clear. In the literature there is no international consensus on how implementation in screening materials should or could be achieved. Randomised controlled trials support the incorporation of interactive videographic information material to arrive at an informed choice. However, the use of such approaches was not evident in practice across any of the countries studied. Such approaches are resource intensive and it may be challenging to adopt expensive approaches in resource constrained environments. Countries included in this project had common features in screening programmes. Accessible and transparent guidance to share across countries may support information production. The process of producing tiered information can also be shared across countries. Regular scheduled updates and quality assessment schemes could support systematic production of information.

10. Recommendations

There is a need for reviewing and updating screening information and quality assurance materials across all formats. The ideal time period between production, review and quality appraisal is unclear, although researchers found a moderate consensus for updating the evidence frequently, for example every 3 to 5 years.

There is a need to develop transparent protocols and/or guidelines to facilitate the production of tiered information for screening. This will encourage best practice and a more standardised approach to customisation.

There is a clear need for implementation research to better understand user needs across different conditions. This includes research to consider and establish resources and constraints for each modality (for example, interactive websites versus paper resources).

Research is required to understand how we can better facilitate the use of evidence-based interventions in practice – specifically interventions which were shown to improve informed choice and knowledge of those people invited to or attending screening as identified by the rapid review.

More research is required to further understand the most acceptable and accessible way to present potentially complex screening information to members of the public (for example, information on prevalence estimates, false negatives and false positives).

Future research should explore standards on how to engage with wider influences to impact informed choice, such as how best to participate in public discussions and respond to public controversies in ways that facilitate informed choice.

11. Authors and funding

Authors: Lena Al-Khudairy, Amy Grove, Abimbola Ayorinde, Iman Ghosh, Laura Kudrna, Natalie Tyldesley-Marshall, Edward James Meehan, Megha Singh, Sian-Taylor Phillips, and Aileen Clarke.

Produced by: National Institute for Health Research (NIHR) Applied Research Collaboration West Midlands (ARC WM).

Source of funding: This research was commissioned by the UK National Screening Committee.

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26. For example: a computer-based worksheet included interactive personal page with aspects leading the choice to participate in screening such as values, experience, and perception of the risk of developing cancer. For each aspect, it can be moved with a cursor against or in favour of participation. The whole page can be downloaded and printed (Roberto 2020). A computer-based worksheet to assist women to weigh up the outcomes and clarify their personal values and preferences (Mathieu 2010). ↩