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The carbon footprint of clinical trials: a global survey on the status quo and current regulatory guidance
  1. Jean-Marc Hoffmann,
  2. Annina Bauer,
  3. Regina Grossmann
  1. Clinical Trials Center, University of Zurich and University Hospital Zurich, Zurich, Switzerland
  1. Correspondence to Dr Jean-Marc Hoffmann; jean-marc.hoffmann{at}usz.ch

Abstract

Introduction All economic sectors including the service sector, along with healthcare, education and research, need to reduce their greenhouse gas emissions to limit global temperature increases. In this study, we aim to globally assess the awareness and current actions taken by Academic Research Institutions (ARIs) or governments regarding the reduction of carbon dioxide equivalent (CO2e) emissions for clinical research.

Methods We designed a cross-sectional survey-based study, which was distributed within the International Clinical Trials Center Network (ICN). The survey population comprised representatives of the ICN who had extensive experience in academic clinical research and profound knowledge and understanding of the local context.

Results The response rate was 80%. Responding ARIs were from 15 different countries and 4 continents. Around half of the ARIs reported that almost none of their research projects considered reducing their carbon footprint. The other half of the ARIs were not familiar with this subject at all. According to 60% of the respondents, greenhouse gas emissions are not assessed by Institutional Review Boards (IRBs)/Ethics Committees (ECs) or competent authorities, while 40% did not know. Neither IRBs/ECs nor competent authorities currently advise sponsors and investigators on reducing the carbon footprint of their clinical research projects. As for reducing greenhouse gas emissions in clinical research, virtual conferences and meetings were the most commonly implemented measures by ARIs across all regions. Finally, we have put together an action plan/checklist advising researchers on carbon footprint reduction for clinical trials.

Conclusion Currently, greenhouse gas emissions are neglected during the planning phase of a research project, and they are not yet addressed or assessed by default during the approval procedures by IRBs/ECs or competent authorities. Thus, all involved stakeholders within clinical research need to be made aware of it through advice from ARIs and IRBs/ECs, among others.

  • environmental health
  • health policy
  • public health
  • cross-sectional survey

Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information.

http://creativecommons.org/licenses/by-nc/4.0/

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

http://dx.doi.org/10.1136/bmjgh-2023-012754

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    WHAT IS ALREADY KNOWN ON THIS TOPIC

    • On a global average basis, the healthcare sector accounts for over 4% of global carbon dioxide equivalent (CO2e) emissions.

    • In July 2023 PubMed showed only seven results when searching for ‘carbon footprint’ AND ‘clinical trials’ within title/abstract.

    • Guidelines like the National Institute for Health and Care Research (NIHR, located in UK) Carbon Reduction Guidelines from 2019 outline approaches to help reduce carbon emissions from health research.

    WHAT THIS STUDY ADDS

    • According to members of Academic Research Institutions (ARIs) worldwide, researchers currently neglect greenhouse gas emissions during the planning phase of research projects. Moreover, CO2e emissions are not yet assessed by Institutional Review Boards (IRBs)/Ethics Committees (ECs) or competent authorities.

    • A high proportion of ARI members do not yet focus on the carbon footprint of clinical research projects as seen by the high number of ‘I don't know’ answers within our survey.

    • No advice from IRBs/ECs or competent authorities is available on reducing the carbon footprint of clinical trials.

    HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

    • Local, national or international consortia such as ARIs and IRBs/ECs need to give advice to all involved stakeholders during the conception phase of a clinical research project or a development programme, on reducing greenhouse gas emissions within the healthcare system.

    • We need to raise awareness in order to increase the pace of action to avert one of the most important global challenges of our time. Long-term change will require sustained commitment by research institutions, regulatory authorities and funding bodies.

    Introduction

    Climate change might be the biggest threat to humanity.1 International efforts such as the ratification of the United Nations Paris Agreement in 2015 are aiming to reduce carbon dioxide equivalent (CO2e) emissions as much and as fast as possible.2 The reduction of CO2e emissions is not only targeted at nature conservation, it could also be shown that limiting global warming will greatly reduce the probability of sustained public health catastrophes.3 4 To achieve this, human-caused CO2e emissions must fall to roughly half of 2010 levels by 2030 and to net 0 by 2050.5

    Worldwide anthropogenic climate change has an influence on physical and mental human health.3 4 6 Examples of the many health impacts include heat-related deaths; changing infectious disease patterns; post-traumatic stress disorder due to extreme weather events and the risk of drought, floods and subsequent food insecurity; and increasing respiratory disease from poor air quality.3 4 It is estimated by the WHO that one in every four premature deaths today is due to environmental factors.6 Vicedo-Cabrera et al showed in their study that warm-season heat-related deaths can be attributed to anthropogenic climate change.7 This clearly illustrates that human health depends on a healthy planet.

    To achieve the goal of reducing CO2e emissions, all sectors, such as transportation, industry, energy and health, must act. Up to now, the spotlight on emissions reduction has been mostly focused on industrial sectors; the carbon footprint of the healthcare industry—and more particularly the pharmaceutical sector—has received little to no attention.8–10 The pharmaceutical sector is responsible for a significant level of environmental damage in the form of greenhouse gas emissions and pollution in the form of excessive discharges.8 9 Belkhir and Elmeligi showed that the pharmaceutical industry is significantly more emission intensive than the automotive industry.9

    In this study, we aim to globally assess the awareness and current actions taken by Academic Research Institutions (ARIs) or governments in regard to the reduction of CO2e emissions for clinical trials.

    Methods

    Study design

    We designed a cross-sectional survey-based study, which was distributed electronically and paper-based within the International Clinical Trials Center Network (ICN).11 The ICN is an international network of academic clinical trial centres built on the core values of Global, Excellence, Harmonisation and Impacts. The mission of the ICN is to enhance the global availability of high-quality clinical research centres and study sites by promoting and supporting the top-level services and proven capabilities of the ICN and its members. This study did not use any personal data from survey respondents. The study does not fall within the scope of the Swiss Human Research Act and hence did not require ethical approval or informed consent.

    Survey conception

    We intended to gather more information about if and how ARIs and their respective country/jurisdiction currently contribute to reducing greenhouse gas emissions for clinical trials. The survey was developed based on a prior literature search on PubMed using the following terms: ‘carbon footprint’ and ‘clinical trial*’, ‘greenhouse gas emissions’ and ‘clinical trial*’, ‘carbon footprint’ and ‘healthcare’ or ‘health care’, ‘greenhouse gas emissions’ and ‘healthcare’ or ‘health care’. The total of six questions were mostly close-ended with Likert-type response options where applicable as well as an ‘I don’t know’ option. For each question, participants had the option to elaborate their answers in a free text section. This survey was conducted as part of an international survey on academic clinical trials and industry sponsored trials with 35 questions in total. The questions were issued in English and were transferred to the REDCap platform12 which allowed us to compose questions on a modular basis. The relevant parts of the survey are published as a supplement to this article (online supplemental file).

    Supplemental material

    Survey population and conduct

    The survey population comprised representatives of ARIs who were members of the ICN network with extensive experience in academic clinical research and profound knowledge and understanding of the local context. On 18 October 2022, invitation emails containing a short instruction and the REDCap web link were sent to the survey participants seeking feedback on the conduct of academic clinical trials versus industry sponsored trials in their institution and in their respective countries/jurisdictions or regions. The survey was open for 3 months and closed on 30 January 2023. Reminders were sent on 16 November 2022, 20 December 2022 and 10 January 2023.

    Data management and analysis

    The quantitative analysis was done by standard descriptive methods such as distribution and percentage calculation using Microsoft Excel (Microsoft Corporation, Redmond, Washington, USA: V.16). The Consensus-Based Checklist for Reporting of Survey Studies (CROSS) was applied for the reporting of this survey.13

    Patient and public involvement

    As this research represents a survey distributed within the ICN, patients were not involved in the design, conduct or reporting of the study.

    Results

    We analysed 20 responses out of the 20 received. As the ICN currently has 25 members, the response rate was 80%. Responding ARIs were from 15 different countries (figure 1): Australia (University of South Australia), Austria (University of Graz), China (Shanghai Clinical Research Center), Germany (Technical University of Munich, Hannover Medical School, University of Freiburg, University of Duisburg-Essen), Hong Kong (University of Hong Kong), Israel (Sheba Medical Centre Hospital), Italy (Alessandria Hospital), Japan (Kyoto University), Nigeria (University College Hospital), Singapore (Singapore Clinical Research Institute), Switzerland (University Hospital Zurich), Taiwan (Hualien Tzu Chi Hospital, Changhua Christian Hospital, China Medical University Hospital), Thailand (Khon Kaen University), Turkey (Istanbul University) and UK (Cambridge University). Characteristics of the participating ARIs are shown in table 1.

    View this table:
    Table 1

    Characteristics of the participating ARIs: (A) location, main function of the respondents and application of the ICH GCP guideline; and (B) clinical trial involvement (in green)

    Figure 1
    Figure 1

    World map representing the countries of the survey respondents in green.

    Participating ARIs were from four continents: Europe, Asia, Africa and Australia. With 18 (90%) out of 20 ARIs, the majority of respondents came from Europe and Asia. Thirteen (65%) respondents worked in a management/leading position within the ARI. All the ARIs apply the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Good Clinical Practice (GCP) guidelines for their clinical trials. Eighty-five per cent of the responding ARIs were involved in phase I, 95% in phase II and phase III and 90% in phase IV clinical trials. Hundred per cent of the ARIs were involved in academic clinical trials, 90% in industry sponsored trials. Non-clinical trials, that is, research involving human data and samples but no testing on humans, were supported by 12 (60%) respondents. North and South America were not represented in our survey. This was due to the location of ICN members with only one ARI located in USA and no ARI in South America.

    Assessment of the carbon footprint for academic clinical trials and industry sponsored trials

    Figure 2A, B shows the percentage of clinical trials focused on a reduction of greenhouse gas emissions. For both academic clinical trials and industry sponsored trials, almost 0% considered reducing their carbon footprint, according to 10 vs 9 (50% vs 45%) respondents, respectively. Only two (10%) ARIs considered the percentage slightly higher with <25%. However, the number of respondents not familiar with this subject was nearly as high with eight vs nine (40% vs 45%) respondents for academic clinical trials and industry sponsored trials, respectively.

    Figure 2
    Figure 2

    Percentage of trials focusing on a reduction of greenhouse gas emissions for (A) academic clinical trials; and (B) industry-sponsored trials; (C) focus on the carbon footprint during submission to IRBs/ECs or competent authorities. EC, Ethics Committee; IRBs, Institutional Review Boards.

    Figure 2C sheds more light on whether or not there is currently a focus on the carbon footprint during submission processes of clinical trials to Institutional Review Boards (IRBs)/Ethics Committees (ECs) or competent authorities. According to 12 (60%) out of 20 respondents greenhouse gas emissions are not assessed. Eight (40%) respondents did not know. At present, neither IRBs/ECs nor competent authorities advise researchers on reducing the carbon footprint of their clinical trials.

    Opinion poll on healthcare sector activities contributing to carbon footprint

    Figure 3 displays the ranking of the respondents about which healthcare sector activities are believed to contribute the most to greenhouse gas emissions. Every respondent was asked to select three answers. Transport & distribution was ranked as the most important with 11 (55%) votes, followed by Operational/Institutional fuel use (9 votes, 45%), Waste treatment (7 votes, 35%), Travel/Employee commuting (6 votes, 30%) and finally Agriculture/Food as well as End-of-life treatment of sold products (1 vote each, 5%). Six (30%) respondents were not familiar with the subject.

    Figure 3
    Figure 3

    Healthcare sector activities believed to contribute the most to the carbon footprint.

    Assessment of measures taken to reduce greenhouse gas emissions of clinical trials

    Figure 4 shows which measures have already been taken both by the ARIs and the respective countries to reduce greenhouse gas emissions in clinical research. Multiple answers were possible. Teleconferencing and/or videoconferencing was the most implemented measure for ARIs with a total of 12 (60%) votes. It was followed by Minimising travelling (six votes, 30%) and Assessment of the carbon footprint of the institution as well as Using renewable energy sources (both five votes, 25%). One other measure mentioned by a respondent was reduction of printing paper and heating. Two ARIs (10%) did not implement any specific measures to reduce carbon dioxide. Five respondents (25%) did not know. As for measures undertaken by the different countries again Teleconferencing and/or videoconferencing was ranked first, Using renewable energy sources second and Minimising travelling and Managing healthcare waste third. Two (10%) respondents agreed that in their country/jurisdiction the carbon footprint of clinical trials was assessed using online calculators for example. Assessing the carbon footprint of clinical trials in grant applications, however, was performed nowhere. According to four (20%) respondents no measure was being implemented in their country, whereas five (25%) respondents did not know.

    Figure 4
    Figure 4

    Measures taken by (A) the respondents’ ARI; and (B) their country/jurisdiction to reduce greenhouse gas emissions of clinical trials. ARI, Academic Research Institution.

    Discussion

    Assessing and reducing the carbon footprint of clinical trials is a topic which a high proportion of our respondents were not familiar with. The majority of academic clinical trials and industry-sponsored trials do not focus on limiting greenhouse gas emissions at all. The carbon footprint of clinical trials seems to only play a tangential role during the daily work of employees from the different ARIs.

    Reducing the carbon footprint in healthcare: a glance at the current situation

    Our participants’ ARIs have reduced greenhouse gas emissions mostly through increased use of teleconferencing and/or videoconferencing. During the COVID-19 pandemic, researchers became more familiar with virtual conferences and day-to-day study meetings and still consider them a valuable alternative to in-person meetings.14 At the 26th United Nations Climate Change Conference in 2021 (Conference of the Parties, COP26) 14 countries, including UK, Belgium, Nigeria and Spain, pledged to develop a carbon-neutral health system by 2050. A further 31 countries, including Argentina, Germany and USA, committed to achieving low carbon, sustainable health systems.15 One year later, during COP27, the US Department of Health and Human Services (DHHS) announced that dozens of health organisations and >1000 hospitals pledged to these goals.16 The need and possibility to lower greenhouse gas emissions also exist in low-income and middle-income countries especially as their carbon footprint is likely to grow with the delivery of commitments to universal health coverage as described by Rasheed et al.17 According to Keller et al the highest CO2e production of an average hospital stems from heating, constituting around 25% of its total carbon footprint.18 Hence, hospitals themselves should increase their use of renewable energies. Moreover, waste prevention and recycling both lower the greenhouse gases emitted during combustion by reducing the amount of waste sent to incinerators and save energy by manufacturing goods from recycled materials, for instance.19 Most of our respondents’ countries/jurisdictions try to reduce greenhouse gas emissions by implementing teleconferencing and/or videoconferencing and using renewable energy sources. The University Hospital Zurich for example is using 100% renewable electricity through wind energy. Sixty-seven per cent of heat use on the campus is covered by CO2-neutral sources such as waste incineration (50%) and wood-burning (17%). Already in 2017, the Swiss Association for Quality and Management Systems (SQS) certified the energy management of the University Hospital Zurich according to the requirements for energy management systems by the International Organization for Standardization (ISO 50001:2011).20 However, none of our respondents have addressed the carbon footprint in clinical trials in grant applications.

    Why are ARIs engaging in as many emission mitigation activities (figure 4A) and similarly reporting such little emphasis among clinical trials they support to reduce their carbon footprint (figure 2A,B)? In fact, ARIs are mostly academic infrastructures connected to universities or university hospitals. University hospitals have already started to reduce their carbon footprint as seen by their pledges during COP26 and COP27 and they are important local economic players, attributing substantial resources to lowering their CO2e emissions. Academic clinical trials, however, are not primarily under the leadership of ARIs, but of an independent sponsor. Often, academic sponsors have no profound education in the field of CO2e emissions. Carbon literacy trainings could become mandatory in the future, similar to GCP trainings. To date, no focus on greenhouse gas emissions has been requested by the authorities, – thus the sponsors did not put it high on their priority list.

    The regulatory authorities and other bodies such as IRBs/ECs involved in the approval of clinical research projects could help in reducing the carbon footprint of clinical trials as well. For now, according to our respondents not a single country/jurisdiction is known in which the IRBs/ECs or competent authorities address the greenhouse gas emissions of submitted projects. In the future, they might include one section in their application form for researchers with a list of measures to reduce their carbon footprint. At present, only a few clinical trials analyse their own CO2e emissions.21–23 According to ICH GCP, all clinical trial protocols need to be approved by IRBs or ECs.24 IRBs or ECs thus evaluate all trials performed in a country independently. The carbon footprint assessment of a clinical trial is also an ethical subject, as climate change is going to have an impact on the health status of all human beings. However, IRBs/ECs currently do not have the resources or knowledge for carbon footprint analysis of clinical trial-related activities. As IRBs/ECs consist of different commissions and members assessing clinical trials, new members specialised in carbon footprint mitigation should become part of the committee. Moreover, international standards for research guidance, such as the Consolidated Standards of Reporting Trials guidelines, should also integrate carbon footprint assessment tools.25 Journals evaluating the research for publication could retrospectively analyse CO2e emissions. They could also require a statement within the manuscript on previously performed carbon footprint assessments, similar to the statement required by the British Medical Journal Global Health on patient and public involvement (PPI).26

    Study activities leading to high emissions of greenhouse gases

    Before planning a clinical trial, extensive research by the study team needs to be performed on primary study registries and reviewing available literature. Interventional clinical studies should only be initiated to solve an unanswered and clinically relevant question. Redundant research projects lead not only to a waste of time and money, but also cause unnecessary greenhouse gas emissions. If a clinical research project is planned, ARIs have an important role: they should address the CO2e footprint when advising/supporting the planning and setup of research projects and encourage researchers to take measures to reduce CO2e emissions. Which activities lead to high emissions of greenhouse gases in clinical trials? A practical way to assess the carbon footprint of clinical trials is the use of online CO2e-calculators such as the ‘Care Pathway Carbon Calculator’ developed by the Sustainable Healthcare Coalition. This calculator takes into account number of patients, patient journeys, bed days within hospitals, surgical procedures and medicine expenditures, among others.27 These tools enable researchers to assess the percentage of carbon reduction by modifying the study design/schedule. A great potential for reducing the carbon footprint of clinical trials lies in the number of on-site study visits. The longer the duration of a study and the more study visits required, the more commuting from participants and investigators is required. Slow participant recruitment due to high volumes of screening failures as well as high dropout rates lead to a prolongation of the study duration and thus increased energy consumption until study completion. PPI during the planning of a study can help researchers in designing study protocols, which are best acceptable and feasible to participants.28 In fact, patient representatives with chronic illnesses have expert knowledge about their disease and know best how to combine study visits with routine medical care: they can advise on adequate numbers of study visits that are tolerated by fellow patients and on the most important patient-reported outcomes; consequently, the number of drop-outs during the study can be minimised. Moreover, PPI during the planning stage can contribute to eligibility criteria, which in turn reduces screening failure levels and reduces higher energy consumption.

    Multicentre studies usually require more shipping of study equipment and travel by study staff, for example, for site monitoring visits. Investigators taking part in international conferences expend a high amount of CO2e. These activities are of course essential for well-functioning clinical trials on investigational medicinal products (IMPs) or medical devices. Nevertheless, researchers should consider minimising travel, developing trials with lower numbers of study visits and consider remote monitoring or study visits at patients’ homes through flying study nurses instead of site visits, if possible.29 Flying study nurses are not bound to one specific hospital, but can coordinate study visits in different medical centres as well as at patients’ homes. Consequently, study visits become more flexible and easier for participants to attend. Remote monitoring most likely depends on the risk rating of the trial in question, and whether it involves an IMP. In the future, a hybrid approach to monitoring, agreed with the sponsor, could be most appropriate. Decentralised trial concepts could support a reduction of the carbon footprint. Guidelines like the National Institute for Health and Care Research (NIHR, located in the UK) Carbon Reduction Guidelines from 2019 outline approaches to help reduce carbon emissions from health research.30

    After the completion of the trial, the sponsors need to enter their results on clinical trial registries like Clinicaltrials.gov31: to date the overall percentage of completed clinical studies with final results available (out of all registered completed trials) was low, with 18% for academic clinical trials and 34% for industry-sponsored trials.32 By uploading their results fellow researchers are updated on the current expertise, avoiding the repetition of similar clinical studies and consequently lowering the emission of unnecessary CO2e.

    Action plan/checklist leading to a reduction in the carbon footprint of clinical trials

    Table 2 summarises measures clinical researchers should implement to reduce the carbon footprint of their clinical trials.

    View this table:
    Table 2

    Action plan/checklist leading to a reduction in the carbon footprint of clinical trials

    Limitations

    We have invested considerable effort to involve academic ARIs from all over the world. We consider the achieved 20 respondents from 15 countries/jurisdictions and the completion rate of 80% to be satisfactory since we could cover most regions worldwide. However, our study findings may not be generalisable to the regions which were not included in the survey. That particularly applies to North and South America that are unrepresented in our results. The majority of our respondents came from Asia and Europe. Furthermore, only representatives of ICN members (that are all academic governmental institutions) were considered for the survey. This led to a relatively small sample size. For future studies it would be interesting to examine how private research institutions and research institutions outside an ICN focus on the carbon footprint of clinical trials.

    Conclusion

    Currently, greenhouse gas emissions of submitted research projects are neither addressed by default nor assessed by IRBs/ECs or competent authorities. A high proportion of ARI members do not focus on this topic, as seen by the high amount of ‘I don't know’ answers within our survey, and no advice comes from IRBs/ECs or competent authorities on reducing the carbon footprint of clinical trials. All involved stakeholders need to be made aware through advice from ARIs and IRBs/ECs, among others, of reducing greenhouse gas emissions within the healthcare system during the conception phase of a clinical research project or a development programme. Clinical trials, that is, both academic clinical trials and industry-sponsored trials, should feel a responsibility to reduce greenhouse gas emissions. However, this reduction should not negatively interfere with the conduct of clinical trials by lowering the quality of their results. We need to raise awareness to increase the pace of action to avert one of the most important global challenges of our time.33 34 Long-term change will require sustained commitment by research institutions and funding bodies. This may have other benefits, such as increased pragmatism in trial designs, better choice of research questions and increased likelihood that trials and development programmes produce important results for global health.21 Achieving net zero should advance the core mission of health institutions that is, improving health.

    Data availability statement

    All data relevant to the study are included in the article or uploaded as supplementary information.

    Ethics statements

    Patient consent for publication

    Acknowledgments

    The authors thank the ICN for encouraging and supporting this project. J-MH thanks Martina Streiff for the fruitful discussions on carbon footprint. We thank Dr Britta Lang, Dr Khadija M’Rabet-Bensalah, Dr Annette Widmann and Joëlle Roos for reviewing the questionnaire. We thank Dr Lucien Gyger for transferring the survey to the REDCap platform. We thank Dr James R Mason for proofreading the manuscript. We gratefully acknowledge the efforts of our survey respondents who participated in this work, namely Dr Carolin Auer, Dr Marta Betti, Dr Christiane Blankenstein, Cedric Bradbury, Sabrina Chen, Prof Susan Hillier, Damien Hong, Shu-Chen Hsu, Chaucer Lin, Prof Tsutomu Nishimura, Dr Atara Ntekim, Prof Christoph Schindler, Louise Stockley, Prof Amir Tirosh, Prof Yagiz Uresin, Ming Wan, Dr Annette Widmann, Prof Henry Yau and Prof Kwanchanok Yimtae.

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    Footnotes

    • Handling editor Seye Abimbola

    • Contributors J-MH, AB and RG contributed to the development of methods and questionnaire. J-MH and AB performed a literature search. J-MH conducted the survey and performed the data analysis and visualisation. J-MH and AB wrote the first draft of the manuscript. RG, AB and J-MH wrote sections of the manuscript. All authors contributed to manuscript revision, read and approved the submitted version. J-MH is responsible for the overall content as guarantor.

    • 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.

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    • Competing interests None declared.

    • Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting or dissemination plans of this research.

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    • 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.