Introduction In connection with a hospital stay, patients have to make important health-related decisions. They need to find, understand, assess and apply health-related information, and therefore, require health literacy. Adequately responding to the needs of patients requires promoting the communication skills of healthcare professionals within healthcare organisations. Health-literate healthcare organisations can provide an environment strengthening professionals’ and patients’ health literacy. When developing health-literate healthcare organisations, it has to be considered that implementing organisational change is typically challenging. In this study, a communication concept based on previously evaluated communication training is codesigned, implemented and evaluated in four clinical departments of a university hospital.
Method and analysis In a codesign phase, focus group interviews among employees and patients as well as a workshop series with employees and hospital management are used to tailor the communication concept to the clinical departments and to patients’ needs. Also, representatives responsible for the topic of health literacy are established among employees. The communication concept is implemented over a 12-month period; outcomes studied are health literacy on the organisational and patient levels. Longitudinal survey data acquired from a control cohort prior to the implementation phase are compared with data of an intervention cohort after the implementation phase. Moreover, survey data from healthcare professionals before and after the implementation are compared. For formative evaluation, healthcare professionals are interviewed in focus groups.
Ethics and dissemination The study protocol was approved by the Ethics Committee of the Medical Faculty of the University of Oldenburg and is in accordance with the Declaration of Helsinki. Study participants are asked to provide written informed consent. The results are disseminated via direct communication within the hospital, publications and conference presentations. If the intervention turns out to be successful, the intervention and implementation strategies will be made available to other hospitals.
Trial registration number DRKS00019830.
- organisational development
- organisation of health services
- medical education & training
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Strengths and limitations of this study
Co-design with healthcare professionals to develop a communication concept.
Mixed-methods study using qualitative and quantitative methods for exploring patients’ and professionals’ needs and experiences.
Implementation of the intervention at the organisational level is a strength; however, at the same time, randomisation is not possible, and therefore, no causal conclusions can be drawn.
Results may not fully apply to patients with particularly low health literacy because self-administered surveys requiring literacy are used, thus a validation of the results is required in the future.
Participant recruitment and concept implementation are vulnerable to the impact of the COVID-19 pandemic.
During a hospital stay, patients have to make important health-related decisions. Therefore, they need to find, understand, assess and apply health-related information and thus require adequate health literacy. However, research in eight European countries has shown that 47% of participants (in Germany, even 54%) have problematic or insufficient health literacy.1 2 Health literacy levels seem to vary depending on sociodemographic characteristics such as sex,3 education,1 socioeconomic status4 and migration status.5 Furthermore, lower health literacy is associated with higher health risks as well as worse patient-reported and health-related outcomes.6 It is widely recognised that health literacy is based on the personal competencies and skills of each individual, but also depends on the demands and complexity of healthcare systems, organisations and living environments.7
Germany’s National Action Plan for Health Literacy7 proposes central strategies for promoting health literacy. Since communication and information deficits are prevalent in healthcare, the action plan calls for, inter alia, improving communication between health professionals and patients.7 Identified problems encompass for example, the use of specialist jargon, lack of time, and a missing or incorrect assessment of patients’ health literacy levels.7 8 By facilitating healthcare professionals’ understanding of health literacy as well as by training healthcare professionals’ communications skills, patient health literacy can be improved and low levels of health literacy of patients can be compensated by adequate communication.9 According to Kickbusch et al.,9 ‘professionals need to tailor their communication to meet the needs of their patients and see it as their responsibility to foster their health literacy’ (p. 16). Apart from this, improving the health literacy of patients requires not only behavioural changes in healthcare professionals, but also wider changes within healthcare organisations.8 The concept of a Health-Literate Healthcare Organisation (HLHO)10 emphasises that health literacy principles need to be integrated into organisational objectives, infrastructure, policies and practices, workforce development and communication strategies. If this is achieved, HLHO can make it easier for patients to find, understand and use information and healthcare services in order to take care of their own health.10 Also, these organisations will have created conditions which are conducive to a good professional–patient communication.
According to a review,11 the success of organisation-wide complex interventions for quality improvement in patient care is often limited by implementation hurdles. Only about 50% of all quality improvement initiatives studied were actually successfully implemented. Due to the lack of consideration of contextual conditions, complex interventions such as interventions to promote a HLHO are often difficult to integrate into everyday clinical practice.12 Implementation research therefore focuses on successful strategies for implementing evidence-based interventions in healthcare. Codesign is a participatory approach to the development of interventions that brings together staff and patient experience13 and has been successfully implemented in a hospital setting by Jessup et al.14 Codesigning interventions and implementation strategies with members of the target group within healthcare organisations can increase implementation success by addressing needs and capacities, identifying barriers and facilitators as well as by fostering organisational change processes.14–16
Principles of the intervention
The intervention encompasses a communication concept consisting of two parts: On the one hand, codesigned communication training for healthcare professionals will be implemented. On the other hand, codesigned supporting measures will be implemented in the hospital environment to improve the conditions for good communication.
The communication training within the presented PIKoG study (As made for us—Improving professional health literacy in hospitals) is based on training units that were developed and evaluated in two previous projects. The original communication training was developed to promote health professionals' knowledge and understanding of health literacy in their patients within the EU study Intervention Research On Health Literacy among Ageing population (IROHLA), which has been successfully piloted in different European countries.17 Results from the pilot study suggest that participation in this training subjectively improved healthcare professionals’ knowledge about health literacy, understanding of health literacy needs, and awareness of the use of jargon. Moreover, the training improved patients’ self-efficacy and resulted in enhanced patient autonomy in the decision making. One of the strengths of this training programme is the diversity of teaching methods used, which have been agreed on among health experts.17 18 Within the EU study IMproving PAtient Centred Communication CompeTences (IMPACCT), the training was adapted to train medical students and nurses.19 20 This communication training, which was previously developed in the IROHLA study and modified in the IMPACCT study, will now build the basis for the co-designed communication training in the presented PIKoG study. In the present study, adaptation to the needs and capacities of hospital employees is achieved in close collaboration with employees with regard to two aspects: the content of the communication training as well as the framework conditions of the training (length, timing, frequency, didactic methods). The training of the present study is conducted by experienced trainers. The research team responsible for evaluation is independent from the communication training team.
The 10 attributes of a health-literate organisation according to Brach et al. offer a conceptual orientation for the development of the supporting measures, which are implemented in addition to the training.10 Possible supporting measures might include the adaptation of the hospital mission statement, integration of the health literacy topic into existing quality management processes,21 placement of posters and other information materials on the wards, providing easy access to health information and services, or designing and distributing print, audiovisual and social media content that is easy to understand and act on.10
Aim of the study
The aim of the study is to codesign, implement and evaluate a communication concept for clinical departments of a hospital. The communication concept aims to improve health literacy at the levels of the healthcare organisation, healthcare professionals and patients.
Method and analysis
Logic model of the study
The logic model (figure 1) that guides the evaluation of the communication concept was developed on the basis of the Medical Research Council Framework for the evaluation of complex interventions.22 Organisational health literacy as the primary outcome is assessed from two perspectives, namely the healthcare professionals’ perspective and the patient perspective.
The study is conducted in acute inpatient care at a university hospital. This non-profit general hospital in north-western Germany offers approximately 400 beds. Four out of eleven clinical departments of this hospital (oncology, gynaecology, orthopaedics and visceral surgery) are participating in the study. The following are the main diagnoses treated at the four clinical departments: hip and knee disorders requiring joint replacement (approx. 750 cases annually), primary breast carcinoma (approx. 300 cases annually), gynaecological tumours (approx. 100 cases annually), lung carcinoma (approx. 100 inpatient cases annually), gastrointestinal tract disorders requiring surgery (approx. 150 cases annually), pancreas disorders requiring surgery (approx. 50 cases annually) and complicated hernias requiring surgery (approx. 35 cases annually). The 3-year study is conducted from October 2019 to September 2022.
The study is conducted in three (partly parallel) phases (see figure 2). In the development phase, a communication concept is designed using a participatory approach. In the implementation phase, this communication concept is implemented in the hospital setting. In the evaluation phase, effectiveness as well as the implementation process is examined in order to identify mechanisms of action and contextual factors.22 The study design entails a quantitative pre–poststudy of experiences and outcomes in patients and healthcare professionals. The formative evaluation uses qualitative methods.
The communication concept—communication training as well as supporting measures—is codesigned with the support of healthcare professionals providing acute inpatient care in different departments of one hospital. This approach takes into account the local context; it allows solutions to be developed that meet the needs of healthcare professionals and are more likely to be acceptable to them and therefore to be adopted and sustained.23
Hospital leaders as change agents
At the beginning of the study, meetings are held with healthcare professionals in leadership positions within the hospital and the clinical departments, who are identified as change agents in a position to drive change. These meetings aim at raising awareness and interest in the study, discussing roles and responsibilities within this study and developing a cooperation agreement. Throughout the study, steering board meetings with these partners are regularly conducted to create a sense of ownership of the study and to coordinate tasks.
Focus group interviews on barriers and facilitators of health literacy-sensitive communication
Focus group interviews (k=4 with healthcare professionals and k=4 with patients, total k=8) are carried out separately for each of the four participating clinical departments (see figure 2). Per participating clinical department, one focus group interview is conducted with healthcare professionals and another with patients treated in the respective department. These interviews aim to identify needs as well as barriers and facilitators to health literacy-sensitive communication (HL-COM) from the perspectives of healthcare professionals and patients. Following existing standards,24–27 a semistructured interview guideline is developed for interviews with both healthcare professionals and patients on needs as well as barriers and facilitators based on their experience. The interview guideline (see online supplemental appendix) is developed based on the framework for patient–professional communication of Feldman-Stewart et al.28 The framework emphasises that the communication between patients and healthcare professionals is influenced by individual characteristics as well as by characteristics of the conversational environment. Focus group discussions are held in German language. To enable the participation of patients without fluent German—a particularly vulnerable group of persons concerning health literacy—translators are asked to accompany those participants. To facilitate valuable discussions, 60–90 min of discussion are aimed at. Group discussions are moderated by two researchers.
Recruitment for the focus group interviews is based on purposeful sampling to cover different facets and perspectives of the discussed aspects. Hospital employees are approached by the hospitals leaders (‘change agents’). Potential participants are then approached by the research team, which provides more information and asks them for written informed consent. Patients are recruited by the research team on the wards on the day the focus group is scheduled. Therefore, patients are informed about the study on the ward and then asked for written informed consent. The focus group interviews (k=4 with n=6–8 persons) with healthcare professionals are heterogeneous in terms of professional groups, sex and age. Healthcare professionals in this study are defined as physicians, nurses, physiotherapists, employees of the psycho-oncological service, social service personnel as well as central patient information staff. Patient focus groups (k=4 with n=6–8 persons) are heterogeneous in terms of sex and age as well as education and migration status2 in order to consider potential health literacy differences.
Employee workshops and facilitator workshops
Methods of organisational development, typically carried out in a participatory workshop format, are used to codesign the communication concept.16 In a participatory format, three employee workshops are conducted to which all healthcare professionals (as defined above) are invited. In the first employee workshop (kick-off), the study goals and approaches are explained to raise awareness and to identify needs. In the second employee workshop, the developed communication concept is discussed to identify potential deficits, while in the third employee workshop, study results are presented and discussed.
Moreover, each participating clinical department is asked to nominate two representatives (‘health literacy facilitators’) for the duration of the study. Representing different healthcare professional groups, they are asked to steer and accompany the codesign and implementation process as multipliers in order to achieve the highest possible reach and acceptance in the departments. Therefore, health literacy facilitators as well as patient representatives (recruited via self-help groups with contact to the clinics) are invited to four facilitator workshops in a participatory format in order to monitor and reflect on the implementation process. To further integrate the patient perspective, patient advocates are invited to participate in the workshops. Patient advocates are volunteers in the hospital who act as contacts for patients’ and relatives’ concerns and are bound to professional secrecy. Focus group participants with interest in the topic can also serve as health literacy facilitators. In the first facilitator workshop, the needs, barriers and facilitators derived from the focus group interviews are presented and jointly discussed to inform the design of the communication concept. In the second facilitator workshop, the designed communication concept is explained and discussed. In the third facilitator workshop, the specific content and the framework conditions of the communication training (duration, timing, frequency, didactic methods) as well as the supporting measures are discussed, and the communication concept is finalised. In the fourth facilitator workshop, the (interim) study results as well as the needs for improvement derived from the formative evaluation are discussed.
The codesigned communication concept will be implemented over the course of a year. The communication training as the central part of the communication concept is offered repeatedly to the healthcare professionals in order to achieve a wide reach within the departments. The training incorporates interactive teaching methods already piloted in IROHLA and IMPACCT, such as case studies, vignettes and role plays.29 To allow constant improvement of the communication training, participants are asked to evaluate each session. In addition to the communication training, supporting measures are to be implemented. In order to increase the use of the supporting measures, they are repeatedly introduced and explained during the communication training sessions. Since the intervention is not fixed beforehand but codesigned together with the healthcare professionals over the course of the study, details cannot be provided at this time.
Patients are eligible for inclusion in the study if they are (1) older than 18 years of age, (2) hospitalised for at least two nights in one of the four participating clinical departments and (3) able to fill in the questionnaires in one of the available languages (i.e., German, English, Russian, Turkish or Polish), either alone or with the support of a friend or relative. Moreover, the study team offers help with filling in the questionnaire to facilitate the participation of illiterate or semiliterate patients. Assignment to the intervention or control cohort is determined by the patients’ treatment period. Patients treated as inpatients in the clinical departments in the last 6 months prior to the start of the implementation phase are recruited for the control cohort. The intervention cohort is composed of all inpatients treated in the clinical departments in the 6 months after the end of the implementation phase. All patients are surveyed longitudinally: at hospital admission (T0), at hospital discharge (T1) and at a 3-month follow-up after discharge (T2).
Based on the annual patient volume of the clinical departments, n=743 patients can potentially be included in each of the two cohorts. In consideration of non-response, we assume that n=500 patients per cohort can be recruited.
Healthcare professional survey
All healthcare professionals of the four participating clinical departments are invited to participate in this study. In addition, healthcare professionals from central facilities, namely physiotherapy, psycho-oncological service, social service and patient information staff, are invited. Healthcare professionals are included if they have routine contact with patients being treated in one of the participating clinical departments. Participation requires sufficient knowledge of the German language (ability to read and complete the consent form and questionnaire). All eligible healthcare professionals (n=240) are surveyed prior to implementation of the intervention and after the intervention. A survey response rate of 50% can be assumed.
Healthcare professional focus group interviews
For the formative evaluation, one focus group interview is held for each of the participating clinical departments, with each focus group being heterogeneously composed of different healthcare professionals according to the criteria of purposeful sampling: physicians, nurses, physiotherapists, employees of the psycho-oncological service or social service as well as patient information staff.
Patient recruitment at hospital admission is handled by the research team. Recruitment of healthcare professionals is carried out with the help of supervisors in the clinical departments and in central facilities within the hospital.
Patients treated as inpatients in the clinical departments in the last 6 months prior to the start of the implementation phase are recruited for the control cohort. The intervention cohort is composed of all inpatients treated in the clinical departments in the 6 months after the end of the implementation phase. To ensure representativeness and comparability of both groups, all patients admitted to the hospital during each of the 6 months are asked to participate. For the patient survey of the intervention and control cohorts, the research team recruits eligible patients on the day of their admission. Care is taken to choose a time when patients are not exposed to increased stress due to the admission processes. A suitable time is determined individually for each clinical department. Patients are given verbal and written information about the study and are asked to give their written consent.
For both the control group and the intervention group, the baseline questionnaire (T0) is handed out, and patients are asked to return the completed questionnaire in a sealable envelope as soon as possible during the first days of their hospital stay. All study documents are explained to potential participants verbally. For patients having difficulties understanding the documents particular time is taken to explain the study, help is offered to fill in the documents together and if possible, support is sought from accompanying persons. For non-German speakers, the study documents are offered in the most common foreign languages in Germany and if needed translators from within the hospital are consulted. The day before their discharge, patients receive the T1 questionnaire and are asked to complete and submit it in a sealable envelope before their discharge. The 3-month follow-up questionnaire (T2), including a stamped return envelope, is sent to the patients' home address by regular mail, with up to two reminders being sent out.30
Healthcare professional survey
For the healthcare professional survey, all eligible healthcare professionals are provided with written study information, a consent form and the questionnaire. Material provision is handled via their supervisors to increase the likelihood of study participation. Participants are asked to return the completed consent forms and questionnaires in sealable envelopes to mailboxes in the hospital. Employees are reminded to participate in the survey via posters attached to the mailboxes.
Healthcare professional focus group interviews
Healthcare professionals are contacted via their supervisors, scientific employees of the participating departments as well as the health literacy facilitators of the study and asked if they are interested to participate. Potential participants are then approached by the research team to inform them about the study and to ask for their written consent. Some workshop participants are also invited to participate in focus groups, if they showed interested. However, the overlap of persons participating in workshops and focus groups is desired to be limited to get additional insights.
Patient surveys include already validated measurement instruments (if available) as well as instruments adapted to the target group and self-developed items (see table 1).
Organisational health literacy as the primary outcome is assessed by means of a patient survey using a validated questionnaire to assess HL-COM.31 Attributes of a HLHO are measured by means of 16 items (Cronbach’s alpha=0.91).31 The general health literacy of patients measured using the German version of the Health Literacy Questionnaire32 is chosen as a secondary outcome (Cronbach’s alpha=0.77–0.91).33 34 As a further secondary outcome, patient-centred care is measured using the subscales ‘appropriate communication’ and ‘personalised information’, which were developed and are currently being validated in the ASPIRED study (Assessment of patient centredness through patient-reported experience measures).35
In this context, a limiting factor of the study is that these instruments have not been validated for patients with particularly low health literacy.
In the intervention cohort the questionnaires include items on the reach of the intervention22 at T1, which are developed based on the actual communication concept to be implemented.
The following sociodemographic and disease-related patient characteristics are collected as context information and potential confounders: sex, age group, education, employment situation, migration status, mother tongue, duration of contact with the German language, chronic diseases, insurance status, disabilities (acquired or congenital), disability severity and degree, healthcare utilisation, diagnosis as indication for hospital stay, duration of hospital stay, transfer between wards, surgery during hospital stay and participation in another study during the hospital stay.
Healthcare professional survey
Healthcare professional surveys include already validated measurement instruments as well as instruments adapted to the target group and self-developed items (see table 1). As the primary outcome, organisational health literacy from the perspective of healthcare professionals is measured using the HLHO 10-item questionnaire (HLHO-10), which was validated using a sample of key persons in hospitals and is available in German (Cronbach’s alpha=0.89).36 The usability of the HLHO-10 to assess change over time has still be proven. Self-reported communication skills as a secondary outcome are measured by an instrument designed by Mackert et al., which consists of 13 items each to be completed before and after communication training.37 It covers perceived basic knowledge of health literacy, ability to deal with individuals of low health literacy and frequency of use of different communication techniques. The instrument is being translated from English to German.
As part of the formative evaluation, questions regarding the achievement of interventional reach, dose and fidelity22 are developed after the communication concept has been finalised. Therefore, items are included to assess the use of the supporting measures for communicating health-related information.
The following sociodemographic data are collected as potential confounders: sex, age group, mother tongue, German language skills, languages which can be used to communicate with patients, highest educational attainment, employment situation, profession, work experience, percentage of working time spent caring for patients, clinical department, participation in training courses during the last year (with and without communication content).
Quality assurance during study execution is safeguarded by the standards of questionnaire development,38 39 pretesting,40 the total design method to increase response rates30 and data processing with the Teleform software (V.16.5.1, Electric Paper Informationssysteme, Lueneburg, Germany). When pretesting the study materials (questionnaires and other documents) care is taken that materials are tested with persons of different health literacy levels to prevent the exclusion of persons with low health literacy.
Healthcare professional focus group interviews
For formative evaluation, guideline-based focus group interviews are conducted. The focus group interviews will be led by two researchers according to a semistructured interview guideline and will last up to 90 min.24–27 The interview guideline for focus group interviews is developed following the existing standards,24 41 study objectives and research questions of the study. Topics are the evaluation of the communication training structure (frequency, duration, didactic realisation), the content of the communication training as well as the supporting measures.
Participation rates and evaluation of the communication training
As part of the formative evaluation, information is collected on the number of communication training sessions conducted and the number of training sessions each healthcare professionals attended. Additionally, every communication training session is evaluated by participants using a short questionnaire.
For the summative evaluation, collected patient survey data of the intervention cohort are compared with the control cohort by using multivariable regression analysis. Possible confounders (e.g., age, sex, diagnosis, comorbidity) are controlled for within the analyses. Collected survey data for the formative evaluation, which refer only to the patient intervention cohort, are analysed, with stratified analyses being conducted for subgroups of patients. Potential differences between the recruited cohorts at T0 will be analysed and adjusted for (e.g., propensity scores).
Healthcare Professional Survey
For summative evaluation, survey data from healthcare professionals prior to the implementation of the intervention are compared with data collected after the intervention using multivariable regression analysis, controlling for possible confounders (eg, profession, work experience). Since the individual survey participants before vs after the intervention are expected to differ to some extent (due to fluctuation, rotation and non-responders), the data are primarily treated as cross-sectional rather than longitudinal within the analysis.
All derived effects are calculated with 95% CIs and corrected for multiple testing. To handle missing data, multiple imputation is conducted.
Healthcare professional focus group interviews
Focus group interview data are analysed by structured qualitative content analysis according to Kuckartz.42 Therefore, audiorecordings are first transcribed verbatim and pseudonymised according to transcription standards.43 First, main categories derived a priori from the interview guideline are developed deductively. Transcripts are then coded and subcategories inductively formed during the coding process. The computer-aided coding of text segments into categories is performed using the programme MAXQDA Analytics Pro (V.2020, VERBI, Berlin, Germany). The entire coding process is conducted by two independent coders, followed by discussions to establish consensus.
Patient and public involvement
Our codesign approach is focused primarily on healthcare professionals since the intervention primarily addresses healthcare professionals and their experiences with patients. In addition, patients are consulted explicitly at different stages of the study. At the beginning of the study, patients as well as healthcare professionals are interviewed about factors that hinder or facilitate HL-COM as well as their needs for improving communication. The results serve as a basis for workshops that are held with healthcare professionals as well as at least one patient advocate in order to select communication training contents and to design supporting measures.
To ensure that the planned measures can be implemented, the hospital’s education management, marketing communication as well as quality management areas are also included in the planning and facilitation process. To facilitate patient participation in the study, the division managers of the wards are also contacted and asked about optimal recruitment times and strategies.
Ethics and dissemination
The study is conducted in accordance with the Declaration of Helsinki in its current version (World Medical Association, 2013). A study protocol was approved by the Ethics Committee of the Medical Faculty of Oldenburg before the study started. All study participants are asked to provide written informed consent based on current data protection regulations. All study participants are informed that participation in the study is voluntary. All personal identifiers are pseudonymised. Data security has been approved by all institutions involved in data collection. The identifying data are stored separately from the research data.
Study results will be summarised in a final report. Moreover, the results will be disseminated in the international scientific community via publications and conference presentations. If the intervention turns out to be successful, the aim is to ensure widespread use of the communication training and to provide a selection of supporting measures to other hospitals. Since the communication concept is implemented in the cooperating clinical departments, patients will be directly affected by and hopefully benefit from some of the supporting measures (eg, easily understandable information leaflets). With regard to study results, posters to be presented in the clinical departments and a press note will be released.
The coronavirus COVID-19 pandemic will influence the conduct and time schedule of the study. Some elements of data collection and possibly the intervention start will have to be postponed by a few months. An extension of the study duration and parallel planning of alternative ways for data collection (eg, using online tools) will ensure the achievement of the study aims. This may, however, result in an adaption of the concrete steps described in the original study protocol.
JSL and MV-B contributed equally.
LA and ALB contributed equally.
Contributors LA, ALB and SL have contributed to the development of this protocol and applied for research funding. LA, ALB and SL developed the analytical strategy and overall methodology, and JSL, MV-B, RLDW, FG, DL, PCOV, JR, DS, GHS, L-AT-d-l-R and DW contributed to designing the study. JSL, MV-B, LA and ALB designed data collection tools and defined the sampling criteria. JSL and MV-B wrote the first andfinal drafts of the protocol. LA, ALB and SL revised all sections of the manuscript and are guarantors. JSL, MV-B, SL, RLDW, FG, DL, PCOV, JR, DS, GHS, L-AT-d-l-R, DW, LA and ALB have read, revisedand approved the final manuscript.
Funding The study is funded by the Federal Ministry of Health on the basis of a resolution of the German Bundestag (grant no. 2519FSB519).
Disclaimer The funder receives all reports but has no ultimate authority over any of these activities, securing good scientific practice and independence of the researchers.
Competing interests None declared.
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.