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Abstract
Introduction Evidence summaries on the benefits and harms of treatment options support informed decisions under controlled conditions. However, few studies have investigated how such formats support decision-making across different social groups. There is a risk that only disadvantaged people will be able to make informed health decisions—possibly increasing the health equity gap. It is also unclear whether they support decision-making in the field at all. The aim of our study is to assess whether evidence summaries based on the fact box format can help people from different social groups make informed decisions about COVID-19 and influenza vaccinations, and thus reduce inequity in health communication.
Methods and analysis In a multi-centre, cluster-randomised, controlled trial, health educators from usual care and outreach work in Germany will be randomised in a 1:1 ratio to provide either usual health communication plus an evidence summary (‘fact box’) or usual health communication. Health educators provide a flyer about COVID-19 or influenza vaccination which contains a link to an online study either with (intervention) or without (control) fact box on the reverse side. Flyer and online study will be available in Arabic, German, Turkish and Russian language. The primary outcome is informed vaccination intention, based on vaccination knowledge, attitudes, intentions and behaviour. Secondary outcomes include risk perception, decisional conflict and shared decision-making. We will use linear mixed models to analyse the influence of both individual (eg, education status) and cluster level factors and account for the expected cluster variability in realising usual health communication or the intervention. The statistical analysis plan includes the selection of appropriate measures of effect size and power calculation, assuming a sample size of 800 patients.
Ethics and dissemination The trial has been approved by the Ethics Committee of the University of Potsdam, Germany (application numbers: 34/2021 and 57/2022).
Results will be disseminated through peer-reviewed journals, conferences and to relevant stakeholders.
Protocol version Version 6 (4 October 2024); Preprint available on Research Square: https://doi.org/10.21203/rs.3.rs-3401234/v3
Trial registration number NCT06076421.
- Decision Making
- Health Equity
- Health Literacy
- Health Services Accessibility
- Randomized Controlled Trial
- Patient Participation
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- Decision Making
- Health Equity
- Health Literacy
- Health Services Accessibility
- Randomized Controlled Trial
- Patient Participation
STRENGTHS AND LIMITATIONS OF THIS STUDY
The intervention was developed in extensive preliminary studies, taking into account the heterogeneity of the target group (Arabic-, German-, Russian- and Turkish-speaking laypeople with different social and linguistic backgrounds in Germany).
The study design enhances the acceptability of the intervention and trust in the communicator by allowing health educators to decide how best to integrate it into their usual care practice.
The involvement of outreach organisations and practices from socially deprived areas warrants the recruitment of disadvantaged participants.
We cannot control for differences in prior knowledge and selection of study participants, as health educators should decide who they want to approach and who not to approach to avoid losing trust.
Introduction
Background
Ensuring informed consent as an ethical principle for medical research involving human subjects is enshrined in the Declaration of Helsinki.1 This consent relies on informed choices for or against medical interventions and requires evidence-based health information (EBHI) being comprehensible and transparent about the benefits and harms of all treatment options.2 3 However, information often fails evidence-based and risk communication criteria,4–6 which means that people facing a health decision are not enabled to make a decision based on evidence-based knowledge and in line with their personal preferences (informed choice).2 One example are package leaflets that are written at a higher reading level and therefore difficult to access, particularly for people with low health literacy or other influencing constructs such as low education7—making informed decisions more difficult. As a result, people are more likely to experience regret, reduced ability to use medicines appropriately and poorer health,2 7 and are less likely to opt for follow-up treatment (eg, booster vaccinations).8 In particular, there are disadvantaged groups in society who make less informed decisions (eg, less educated, non-native speakers)9–11—leading to inequities.
To reduce inequities and achieve high-quality healthcare, the structures in the healthcare sector and approaches (eg, communication formats and channels for patient education) must enable disadvantaged people to access and navigate the health system for effectively managing their health and care.12 Patient-oriented information such as EBHI and decision aids (DAs) are key elements in improving health communication and thus healthcare by enabling more people to make informed and shared decisions.13 The benefits of such information over standard care (no evidence-based information or no intervention) are already clear. A Cochrane review14 found that DAs have a positive effect on knowledge, information and perception of values, and that decision makers are likely to take a more active role in the decision-making process and have a better perception of risk.14 However, there is a risk that only certain groups of the population will benefit from EBHI and DAs. Even if materials are ‘target group-oriented’, the factors that lead to inequity in terms of shared and informed decision-making have not yet been sufficiently taken into account in their development process.9 15 For example, there are many patient-oriented materials written at an advanced level, which makes them less accessible to people with reading difficulties, lower education or health literacy.7 16 17 Overall, only few studies have looked specifically at the impact of shared decision-making (SDM) or informed decision-making in groups that are more likely to have communication barriers due to their racial or ethnic background and/or level of education.15 18
Objectives
The aim of our study is to assess whether evidence summaries using the fact box format can facilitate informed decisions for laypeople from different social backgrounds. Further, we explore whether these fact boxes contribute to reducing inequity in healthcare—with the help of shared decision-making.
Fact boxes provide a tabular or graphical overview of the benefits and harms of medical options through transparent risk communication.19 They are used to inform a range of health decisions, such as medical treatments, cancer screening and vaccinations (see https://hardingcenter.de/en/transfer-and-impact/fact-boxes). In contrast to DAs, fact boxes do not contain preference elicitation. By reducing complexity and balancing evidence, they aim to promote informed decisions instead of predetermined behavioural change (eg, having a vaccine).20 Consequently, they are in line with those Western health standards and ethical principles that differ from persuasion or nudging, which can be at odds with informed choice and pose the risk of undermining the trustworthiness and credibility of the communicator and vaccinator.20 21 Fact boxes are developed according to the Medical Research Council guideline Development and Evaluation of Complex Interventions.22
Several experiments have shown that fact boxes support informed decisions by improving, for example, risk perception, short-term knowledge and knowledge recall, and comprehension.20 23–28
At present, it is unclear whether fact boxes can be an effective format outside (online) laboratory conditions. Further, fact boxes have been tested with the lay public, but only three studies analysed its effect by vulnerability factors.20 25 26
Additionally, our study should reveal to what extent evidence-based summaries using the fact box format can be integrated into the communication of health educators (eg, doctors) in standard care and outreach settings, and what added value they have in supporting SDM compared with conventional information or no information at all.
Although there is evidence for the benefits of SDM interventions (eg, EBHI) in improving people’s knowledge of risks and benefits, feeling informed and clarity about their values in a variety of decision-making contexts,14 and thus for their use in clinical practice, the real-world effects of implementing EBHI as an SDM intervention are still unclear. What are the prerequisites, facilitators and barriers for people to benefit from them in practice? What are the prerequisites and barriers for clinicians to implement them? Already in 2013, the authors of a review called for more research into the extent to which EBHI and DAs are effective in medical care, as they are not yet widely used in medical practice.29 Moreover, in 2019 only 21% of DAs were introduced after trials and a further 7% were part of implementation studies. Barriers included outdated evidence in DAs and disagreement among clinicians about the use of DAs.30
This paper reports on the study protocol of an implementation study and equity evaluation of evidence-based summaries on COVID-19 and influenza vaccination in different health education settings in Germany using fact box formats. The trial was prospectively registered on clinicaltrials.gov (NCT06076421).
Acknowledging that public health initiatives generally aim to promote vaccination to protect the population from vaccine-preventable death and disease (societal perspective), individual autonomy and informed choice are ensured in many health systems (eg, ‘the 2013 German Patients' Rights Act’3). Therefore, the aim of health campaigns is also to provide comprehensive information about the benefits and harms of vaccination, to consider the needs of citizens and patients, and to increase transparency and individual understanding of the social benefits of vaccination through education (see also Goal 3 of the U.S. Vaccines National Strategic Plan31). Improving public understanding of vaccination policy in order to strengthen trust and compliance is crucial for future positive vaccination behaviour—particularly so in the case of seasonal vaccinations.
Thus, the study will provide insights into the extent to which non-directed evidence summaries, with a focus on supporting informed decision-making, can contribute to achieving public health goals. The study will therefore be of interest to other organisations that produce health information and is thus relevant to both producers and disseminators of health-related information, as well as to decision-makers at various levels who develop strategies to achieve societal goals for maintaining and promoting public health.
Methods and analysis
The protocol follows the SPIRIT 2013 guideline32 and CONSORT Equity Reporting Guideline 2017.33 33
Design and setting
We will conduct a cluster randomised controlled trial with a 2×2-between-subjects design: format (usual health communication plus fact box vs usual health communication) and health educator (cluster unit medical practice vs cluster unit outreach work settings) (figure 1). Health professionals in particular are still the first-contact for people seeking health information in Germany.34 Therefore, the cluster units will include all those who communicate about health issues (eg, doctors and other health professionals, community health workers) in Germany, as well as settings where traditional communication about disease prevention takes place (eg, doctors’ offices) and where communication about health issues is carried out in the context of outreach work (mothers’ and fathers’ cafés, intercultural meeting places) if more than one person per unit participates. We will refer to these units as health educators. The study started in November 2023, and data collection is expected to be completed towards the likely end of the influenza season in Germany (Spring 2025).
Study design.
Research questions
Do disadvantaged people benefit to the same extent as non-disadvantaged people in terms of informed and shared decision-making from receiving COVID-19 and influenza vaccination fact boxes as opposed to standard vaccination communication in medical practices and outreach work (field settings)?
Disadvantaged populations
In order to reduce inequities in healthcare, it should be recognised that certain individual and sociocultural factors affect health opportunities and outcomes and lead to disadvantages in the impact of interventions. These factors are defined within the PROGRESS framework as place of residence, race/ethnicity/culture/language, occupation, gender/sex, religion, socioeconomic status and social capital.35 Ignoring them can exacerbate health inequalities, even if public health interventions (eg, education, communication and information) are generally effective.36 For examining the impact of our intervention, we take the following factors and concepts into account (table 1): education, subjective socioeconomic status (SSS), health literacy as well as mother tongue (German, Arabic, Turkish, Russian, other) and language (subjective native reading literacy, perception of own German language skills).
Criteria for defining study participants as being disadvantaged
Research questions (RQ) and main hypotheses (HYP)
RQ1
Is the use of fact boxes more effective than standard communication (control condition) in the field?
Primary HYP. We hypothesise that compared with standard vaccination communication implementation of fact boxes in medical practices and outreach work will lead to:
Higher vaccination knowledge: A number of studies have shown that fact boxes improve short-term knowledge and recall and comprehension,20 23–26 enabling people to weigh the benefits and harms of an intervention.
More vaccination intentions that are in line with attitudes and vaccination knowledge (informed vaccination intentions): Because knowledge is a component of informed choice and attitudes about vaccines’ benefit–harm ratios are not biased by the presentation of a vaccine fact box.20
Secondary HYP. We hypothesise that compared with standard vaccination communication implementation of fact boxes in medical practices and outreach work will lead to:
Improved risk perception: One study found that studying fact boxes can improve accuracy of COVID-19 risk perceptions without affecting vaccination intentions.20
Increased patient involvement in medical decision-making: As based on data from a Cochrane Review evidence-based tools aimed at enabling informed decision-making have the potential to increase patient involvement.14
Decreased decisional conflict: A study24 found that, compared with controls, participants who received fact boxes experienced less decisional conflict about antibiotic use (non-standardised beta (β) = −8.35, 95% CI, −12.43, −4.28) and artificial hydration (β = −6.02, 95% CI, −9.84, –2.20) at 1 month compared with baseline.
RQ2
Are fact boxes as effective for people with disadvantaging factors as for those without those factors?
HYP. We will analyse the effect of fact boxes compared with usual care among people with more and less advantaging factors (eg, in terms of education), taking into account known baseline differences between advantaged and disadvantaged people. The added value of evidence-based tools (eg, DAs) over traditional (non-evidence-based or usual) healthcare and interventions tailored to specific target groups (eg, people with low levels of education) has already been demonstrated.14 18 We therefore expect that the gap will narrow between more and less advantaged people in terms of outcomes relevant for informed vaccination decisions. We hypothesise that the implementation of fact boxes compared with standard vaccination communication will lead to a greater alignment of knowledge, informed vaccination intentions and accuracy of risk perception between:
People with low and high education.
People with problematic or inadequate and excellent or sufficient level of health literacy.
Non-native (Arabic, Turkish and Russian speaking participants, only with low German skills) and native German speakers (including non-native speakers with high German skills), because we not only provided information in the native language but also tested it with these target groups.
People with low and high reading literacy in different languages, because fact boxes are a complexity-reduced format of health information and we tried to address accessibility through pilot testing with different groups.
RQ3
Does the use of fact boxes in outreach work promote more shared and informed decision-making than in regular healthcare settings?
HYP. We assume that fact boxes more likely lead to more informed vaccination intentions and shared decisions in outreach work than in regular healthcare settings. In order to respond to the needs of especially people with disadvantaging factors and to reach them in a more effective way, community-based health services are becoming more and more important.37 The use of non-primary care professionals (eg, social workers, community nurses or community health workers) who can build trust and provide psychoeducational interventions has been shown to be effective in providing health knowledge, improving healthcare, changing health behaviour and improving health status.37 38
Explorative analyses
We will analyse the effect of fact boxes on knowledge, vaccination intentions and accuracy of risk perception between people with low and medium or high SSS through fact boxes compared with usual vaccination communication.
We will analyse the effect of fact boxes on vaccination intentions, knowledge, risk perception, patient involvement and decisional conflict among people with migration-related indicators (eg, residential status, length of stay in Germany) compared with usual care, controlling for other factors describing the social situation (eg, education, health literacy). This may be crucial because people with immigrant history are less receptive to information from authorities or health providers in Germany, the host country (even if it is translated), if they have less trust in them.39 Also campaigns or formats that work for the majority of the host population may not be the right channel for communicating with immigrant groups.39 An increased length of stay is associated with a greater orientation towards the host society and thus a change in lifestyle habits, health perceptions and health behaviour.40 41 On the other hand, a shorter duration of stay, as well as not having German citizenship or a residence permit, may be associated with higher barriers to access to the German healthcare system (eg, due to lack of insurance or more difficult access to (multilingual) health information).40
Eligibility and recruitment strategy
Study participants in general
The trial is open to people who are currently facing a decision about vaccination for themselves or a family member (eg, caring relatives). Adults of legal age with current residence in Germany and who speak German, Russian, Turkish or Arabic will be included. All participants must confirm their informed consent online to take part in our study. Patients who do not speak any of the four languages and who do not give informed consent will be excluded.
Health educators will be asked to inform all potential participants about the study. The health educators will then distribute the study flyer as part of the health communication or afterwards. To ensure sufficient variability of a potential disadvantage status, the recruitment of health educators is focused on facilities and practices that serve a very heterogeneous audience. In particular, involving outreach organisations will ensure that disadvantaged people who are underserved are reached. In addition, health educators will be sensitised to approach these groups but will also be selected on the basis of their geographical area, for example, in districts with higher socioeconomic deprivation (socioeconomic differences that lead to differences in health outcomes).42 In addition, health authorities will be asked to help identify facilities and practices that primarily serve a disadvantaged population.
In order to make the study as accessible as possible for the target group, information about the study and about data protection will be provided in their preferred and in plain language. Those who decide to take part in our study will complete an online survey. There will also be a read-aloud function for the questionnaire in all languages. After completing the initial online survey (T1), participants will have the opportunity to provide their email address for a follow-up survey 4 weeks later (T2). At the end of this second survey, participants will be rewarded with a voucher worth 15 Euro.
Health educators
Key requirement for involving health educators is that they provide information on health-related topics and have access to potential study participants. Furthermore, informed written consent is a prerequisite.
To reach health educators, we will contact German public health authorities and ask them to distribute the study call to all kinds of health educators in their respective areas of responsibility (districts). We will also directly contact potential health educators by email or post. All health educators will first be given general information about the study and asked for their consent.
Health educators will not be remunerated. Our study will be conducted in close cooperation with the health departments in Germany, which provides access to the planned cluster settings and the target groups.
Intervention
Health educators in the intervention group will receive a flyer with a brief description of the study, a QR code and a link to an online survey, including on the reverse side a fact box about COVID-19 or the influenza vaccine in Arabic, German, Russian or Turkish.
In several prestudies, the intervention underwent a comprehensive development process. This included feedback from various public health stakeholders on a COVID-19 fact box implemented in January 2021 by the Robert Koch Institute, the German national health authority. Further, information needs and requirements of the population in Germany were incorporated in updates20 with the help of secondary data analyses.
Simplified COVID-19 and influenza vaccination fact boxes were tested for comprehensibility in 52 cognitive interviews43 between July 2021 and September 2022. First, a tabular COVID-19 fact box was tested with German-speaking participants and translated into a visualised fact box, which was then tested with Arabic-, Turkish- and Russian-speaking participants from disadvantaged districts of Berlin. Cognitive interviewing methods43 were used to ask whether the information in the fact boxes was understood and how it was understood. This method is usually used to pretest questionnaires. In individual interviews by telephone (during the COVID-19 period) and in person, a partially standardised questionnaire was used to ask respondents to reproduce the content of the fact boxes and to identify any comprehension problems in terms of content and wording. A visualised influenza fact box was piloted by the University of Erfurt with German-speaking laypeople with low numeracy.
The non-directional vaccination fact boxes will be available either in tabular form (for influenza) or as a visualisation (for COVID-19), each in all languages and for both age groups. COVID-19 and influenza vaccine fact boxes are available for two different age groups each: COVID-19 vaccination for people aged 18–59 and over 60; influenza vaccination for people aged 16–64 and over 65. Accordingly, the study neither compares fact box formats (tabular, visual) nor examines disease-specific effects.
Health educators are free to decide if and how to use the fact boxes, whether during, before or after vaccination education and whom to address. Therefore, there will be no training, as we cannot expect a one-size-fits-all solution for all health educators in different settings and especially in outreach settings (which are very heterogeneous). By asking health educators about their use of the fact boxes as part of a telephone assessment at the end of the study, we want to find out if and how they can be implemented in usual care.
Control condition
Health educators in the control condition will also receive the flyer with a brief description of the study, a QR code and a link to the online study to distribute to potential study participants, but without the fact box on the back.
Patient and public involvement
As described in the Intervention section, the COVID-19 and influenza vaccination fact boxes were developed through a comprehensive process involving various stakeholders and in particular the target groups, at all stages: (1) Information needs and requirements of the population in Germany were incorporated in updates20 with the help of secondary data analyse, (2) Simplified COVID-19 and influenza tabular vaccination fact boxes were tested for comprehensibility in 52 cognitive interviews43 with German-, Arabic-, Turkish- and Russian-speaking participants from disadvantaged districts of Berlin and (3) A visualised influenza fact box was piloted with German-speaking laypeople with low numeracy.
The study design, outcomes, strategies for reaching vulnerable target groups and the questionnaire were discussed with various expert groups (eg, scientists from different disciplines, representatives of health authorities and outreach work).
Randomisation and allocation concealment
First, health educators will be randomised, either at the individual level or at the institutional level if there is more than one health educator per setting. Health educators who gave written informed consent will be assigned a study ID number and randomly assigned to one of the two study conditions: (1) usual health communication plus fact box (intervention) or (2) no information/usual health communication (control) (see figure 2) by an independent researcher using computer-generated random numbers in a 1:1 ratio. Health educators will then distribute their assigned flyer format to individuals who are about to make a vaccination decision about the COVID-19 or the influenza vaccine, taking into account their reference group (age group).
Study allocation and data collection.
Blinding
Health educators and study participants will not know which study condition they belong to. Health educators will be assigned by a person independent of the study, which means that the assignment will be blinded. Health educators in the control group will also have the opportunity to receive the fact boxes for their health communication post-trial. The data analyst will also be blinded.
Outcomes
Health educators
Preintervention the type of health education setting (doctor’s office or outreach work (alone or in a community setting/group practice)) is registered. Health educators will be asked about perceived changes in vaccination behaviour from the start of the intervention, once a cluster is no longer recruiting. Health educators will be asked about their demographics (age, gender, mother tongue) and, in the intervention group, how they used the fact boxes (during, before or after vaccination communication) and about involving patients from their perspective (SDM-Q-Doc).44
Participants
Sociodemographic information and outcomes will be collected after people receive the flyer from their health educator and access the study link or QR code. As the study is voluntary and those who approach people do not know who among those approached will participate in the study, we will not be able to control who participates in the study and we will not be able to follow-up with those approached unless they complete the first survey. All information will be collected at the time of the first survey (T1), as participation in the second survey (T2) 4 weeks after the initial survey is also voluntary.
The primary outcomes (online supplemental table S1) are knowledge and informed vaccination intention. For exploratory purposes, we will analyse on knowledge differences on the item level. The secondary outcomes are risk perception, decisional conflict and patient involvement (online supplemental table S2). Furthermore, we will collect sociodemographic information, SSS,45 migration history and health literacy46 (online supplemental table S2). Study participants will be also asked whether the fact box was used as part of the counselling process and how they judged it.
Supplemental material
Sample size
We aim to demonstrate moderate main effects (equal to Cohen’s d=0.50) of the study intervention on informed intentions (10% expected in usual care) and a knowledge sum score (equal to the proportion of correct responses; with an expected variance of 0.20). Taking into account a cluster correlation coefficient (ICC=0.10) common for primary care studies with patient endpoints,47 we will target three health educators (eg, doctors’ offices) per study arm with 40 patients/clients per health educator.48 So, 240 participants in each subgroup undergoing the same analysis are required (online supplemental table S3). Furthermore, to demonstrate small-to-moderate interaction effects (equal to Cohen’s d=0.375) of the study intervention in respective settings on informed intentions and knowledge, we have to target instead seven health educators per study arm with 40 patients/clients per health educator (n=560). In total, we aim at 800 participants because the proportion of subgroup members cannot be predicted, and we cannot rule out that interaction effects in the field are smaller than expected from experimental evidence (eg, d=0.20 would call for up to 20 health educators per study arm). Further details on the assumptions underlying the sample size calculations in the power calculation with respect to the critical hypotheses and outcomes are provided in online supplemental table S3 in the supplementary section.
Data collection and management
After giving their online consent, participants will complete an online survey via SoSciSurvey. The survey (T1) is completely anonymous for the study participants. Personal data (email address) will be only collected if there is interest in participating in the follow-up survey (T2) and in the remuneration, for which also first name and surname will be recorded. For this purpose, a computer-generated random ID will be generated by someone independent of the study, which is stored with the unblinding list separately from the collected personal and survey data at the Harding Center (HC) on password-protected computers and is only accessible to researchers of the HC until the end of the data collection.
The survey of the health educators will be conducted under pseudonym. The random generated ID, personal and survey data will be separated from the contact information immediately after completion of the postsurvey, and the de-blinding list is also kept until the end of the data collection.
All relevant data will be provided in the manuscript and supporting information or made available in a public repository after the completion of the study.
Statistical analysis
Data analysis will initially be based on descriptive statistics as well as frequency distributions and histograms to identify outliers and missing data. Baseline data of the study arms will be compared to see if the distribution is balanced between study sites/clusters. SPSS will be used to conduct all analyses.
All participants will be asked to indicate at T1 whether they received the intervention to allow for intention-to-treat and as-treat analyses.
Statistical methods for analysing primary and secondary outcomes
We use linear mixed models to analyse the influence of both individual (eg, education status, health literacy) and cluster level factors (eg, setting) and account for the expected cluster variability in realising usual care or the intervention (details are outlined in online supplemental table S4).
Missing data
We will record the number of flyers distributed per cluster. Because participation is voluntary, anonymous and not aware to the health educators, we will not be able to send a reminder and record the response rate for those who were approached. We will record the numbers of the total randomised sample for each group as well as the reasons for exclusion. It is compulsory for participants to answer all questions within the surveys. As participation in the follow-up survey is voluntary, we will record the number of drop-outs from the first to the second survey.
Ethics and dissemination
The trial has been approved by the Ethics Committee of the University of Potsdam, Germany (application numbers: 34/2021 and 57/2022). Written informed consent will be obtained by the health educators prior to randomisation. Informed consent will be obtained online from study participants and/or their legal guardians after opening the QR code/link to the study on the flyer, and all study and ethical information has been provided (see online supplemental S1 for an example).
Supplemental material
Any changes to the protocol that affect the conduct of the trial, as well as changes to the study design, patient population, sample size, primary outcomes or statistical analysis plan, will be made transparent in the trial registration and final report.
We plan to disseminate our findings through publications in peer-reviewed journals, national and international conferences, and relevant working groups and networks (eg, German Network for Evidence-Based Medicine, German Society for Public Health and Population Medicine), also targeting relevant community stakeholders.
Ethics statements
Patient consent for publication
Acknowledgments
We would like to thank the Robert Koch Institute and Christoph Wilhelm for the initial development and further development of the materials that we will use in the study. We would also like to thank those who provided valuable feedback on early drafts of the fact boxes and Marike Pohlmann from the University of Erfurt, who tested the visualised flu fact box with German-speaking people with low numeracy skills as part of her master's thesis. And we would like to thank Professor Dr Rahim Hajji from the University of Applied Sciences Magdeburg-Stendal for his constructive feedback on the study design and the operationalisation of vulnerability characteristics. We would also like to thank Tobias Prey from the Berlin Mitte District Office, Department of Quality Development, Planning and Coordination of the Public Health Service for his support in recruiting health educators.
References
Supplementary materials
Supplementary Data
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
Footnotes
X @nicolaisavaskan
Contributors CE and FGR designed the study. FGR has developed the statistical analysis plan. All authors conceptualised and designed the protocol. CE wrote the first draft of the manuscript and made the revisions. NS and FGR contributed to and critically revised the manuscript. All authors finally approved the manuscript. CE is the guarantor for this study protocol.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.