Overdiagnosis is increasing the carbon footprint of healthcare

Diagnostic Excellence in the Context of Climate Change: A Review

Climate change is leading to a rise in heat-related illnesses, vector-borne diseases, and numerous negative impacts on patients' physical and mental health outcomes. Concurrently, healthcare contributes about 4.6% of global greenhouse gas emissions. Low-value care, such as overtesting and overdiagnosis, contributes to unnecessary emissions. In this review, we describe diagnostic excellence in the context of climate change and focus on two topics. First, climate change is affecting health, leading to the emergence of certain diseases, some of which are new, while others are increasing in prevalence and/or becoming more widespread. These conditions will require timely and accurate diagnosis by clinicians who may not be used to diagnosing them. Second, diagnostic quality issues, such as overtesting and overdiagnosis, contribute to climate change through unnecessary emissions and waste and should be targeted for interventions. We also highlight implications for clinical practice, research, and policy. Our findings call for efforts to engage healthcare professionals and policymakers in understanding the urgent implications for diagnosis in the context of climate change and reducing global greenhouse gas emissions to enhance both patient and planetary outcomes.

What Australia must do to create a climate-responsive health system

COP-28, the United Nations' Climate Change Conference, hosted by the United Arab Emirates, ended on 12 December 2023. At the convention, Australia released its National Health and Climate Strategy, committing to low-carbon, climate-responsive care. The Strategy will need new policies, projects and investments and a fit-for-purpose health workforce. This is a tall order considering healthcare's challenges. Everyone has a role, including clinicians, healthcare agencies, policymakers, politicians, patients and the providers and manufacturers in the supply chain. Clinicians' groups, policymakers and federal and state departments of health have an opportunity to lead climate change reform by considering climate change impacts across clinical practice and health policy.

Sleep-disordered breathing diagnosis: a comprehensive audit of home sleep testing in real clinical settings

PURPOSE

This study aimed to investigate the indications and outcomes of Home Sleep Testing (HST) for patients with suspected obstructive sleep apnea (OSA), aligning with guidelines set forth by the American Academy of Sleep Medicine and the European Sleep Research Society. Specifically, we aimed to audit whether validated type 3 polygraphy could effectively ensure patient care while optimizing resource utilization.

METHODS

A retrospective analysis was conducted on data from patients undergoing type 3 polygraphy for suspected OSA in a tertiary referral hospital between January 2022 and December 2022. Demographic, clinical, and management data were collected. The efficacy of HST in guiding management plans was evaluated, with outcomes categorized as effective or ineffective based on subsequent need for in-laboratory polysomnography.

RESULTS

While 85% of patients received a reliable diagnosis, 44.4% of them still required subsequent polysomnography, primarily due to adherence to funding regulations, rather than clinical need for further testing. Factors impacting the efficacy of HST included patient age, severity of apnea, and referral by a certified sleep specialist physician.

CONCLUSION

Our study highlighted the potential of type 3 polygraphy, as a valuable tool for diagnosing OSA in an outpatient setting. However, having the result interpreted by a certified sleep specialist doctor was not enough. To streamline the care pathway, the referral for polygraphy had also to be made by a trained specialist. Challenges related to funding regulations, patient demographics and physician training stress the need for optimized diagnostic pathways to improve patient care and resource utilization.

The role of planetary health in urologic oncology

INTRODUCTION

Climate change and global warming are an omnipresent topic in our daily lives. Planetary health and oncology represent two critical domains within the broader spectrum of healthcare, each addressing distinct yet interconnected aspects of human well-being. We are encouraged to do our part in saving our planet. This should include the decisions we make in our professional life, especially in uro-oncology, as the healthcare sector significantly contributes to environmental pollution.

AREAS COVERED

There are many aspects that can be addressed in the healthcare sector in general, as there are structural problems in terms of energy consumption, water waste, therapeutic techniques, transportation and drug manufacturing, as well as in uro-oncology specific areas. For example, the use of different surgical techniques, forms of anesthesia and the use of disposable or reusable instruments, each has a different impact on our environment. The literature search was carried out using PubMed, a medical database.

EXPERT OPINION

We are used to making decisions based on the best outcome for patients without considering the impact that each decision can have on the environment. In the present article, we outline options and choices for a more climate-friendly approach in urologic oncology.

Blood over-testing: impact, ethical issues and mitigating actions

Plenty of studies demonstrate that hospital-acquired anemia (HAA) can increase transfusion rates, mortality, morbidity and cause unnecessary patient burden, including additional length of hospital stay, sleep disruption and venipuncture harms resulting from blood samples unlikely to change clinical management. Beyond patient costs, community costs should also be considered, such as laboratory time and resources waste, environmental impact, increasing pressure on labs and fewer tests available on time for patients who can benefit from them most. Blood over-testing does not support the principles of non-maleficence, justice and respect for patient autonomy, at the expense dubious beneficence. Reducing the number and frequency of orders is possible, to a certain extent, by adopting nudge strategies and raising awareness among prescribing doctors. However, reducing the orders may appear unsafe to doctors and patients. Therefore, reducing blood volume from each order is a better alternative, which is worth implementing through technological, purchasing and organizational arrangements, possibly combined according to need (smaller tubes, adequate analytic platforms, blind dilution, blood conservative devices, aggregating tests and laboratory units).

Mapping the Environmental Co-Benefits of Reducing Low-Value Care: A Scoping Review and Bibliometric Analysis

Reducing low-value care (LVC) and improving healthcare's climate readiness are critical factors for improving the sustainability of health systems. Care practices that have been deemed low or no-value generate carbon emissions, waste and pollution without improving patient or population health. There is nascent, but growing, research and evaluation to inform practice change focused on the environmental co-benefits of reducing LVC. The objective of this study was to develop foundational knowledge of this field through a scoping review and bibliometric analysis. We searched four databases, Medline, Embase, Scopus and CINAHL, and followed established scoping review and bibliometric analysis methodology to collect and analyze the data. A total of 145 publications met the inclusion criteria and were published between 2013 and July 2023, with over 80% published since 2020. Empirical studies comprised 21%, while commentary or opinions comprised 51% of publications. The majority focused on healthcare generally (27%), laboratory testing (14%), and medications (14%). Empirical publications covered a broad range of environmental issues with general and practice-specific 'Greenhouse gas (GHG) emissions', 'waste management' and 'resource use' as most common topics. Reducing practice-specific 'GHG emissions' was the most commonly reported environmental outcome. The bibliometric analysis revealed nine international collaboration networks producing work on eight key healthcare areas. The nineteen 'top' authors were primarily from the US, Australia and Canada.

Medicalization of Old Age: Experiencing Healthism and Overdiagnosis in a Nordic Welfare State

In Denmark, people are expected to take responsibility for their health, not least as their bodies age and they experience signs of physical or mental decline. Drawing on fieldwork among older Danes, I illustrate that an excessive focus on health gives rise to social and structural controversies and disparities, linking ideas of healthy behavior at the individual level with the societal framing of disease and aging. I argue that this emphasis contributes to the unwarranted diagnosis of bodily variations that naturally occur in the aging process, a phenomenon referred to as overdiagnosis, adding to a broader medicalization of old age.

Reducing reflex first-line prescriptions in a surgical pathology laboratory: toward sustainable practice with positive economic and clinical effects

In surgical pathology departments, reflex first-line techniques (RFLTs) are aimed at reducing workloads and addressing recent shortages of medical personnel. However, the impacts thereof on economic and diagnostic factors have been poorly addressed. Also, in the era of global warming, environmental considerations are crucial. This study assessed the economic and diagnostic efficacies of routine pathological RFLT and the quality of care and sustainability. Ten RFLTs of the Bordeaux University Hospital pathology department (six special stains, one cytology technique, and three immunohistochemical tests) were studied. First, a retrospective economic analysis evaluated the average cost of these RFLTs per slide and per year. Second, diagnostic relevance was prospectively surveyed. Third, the effects of changes made were analyzed over 2 years. The ten RFLTs were associated with average annual costs of €46,708. Diagnostic relevance analysis indicated that most stains were unnecessary; only 17% were requested as second-line techniques. Elimination of 7/10 tests afforded annual cost savings of €22,522 and reduced the workload by 5568 tests/year, without compromising the workflow or diagnostic quality. Seven of ten RFLTs could be eliminated without compromising diagnostic quality or the workflow. This afforded not only financial benefits but also positive social and environmental impacts. We offer valuable insights into appropriate practices in surgical pathology laboratories. Collaboration between the medical and technical teams was crucial; other healthcare sectors would also benefit from our approach.

Overdiagnosis in malignant melanoma: a scoping review

OBJECTIVES

We aimed to systematically identify and scrutinise published empirical evidence about overdiagnosis in malignant melanoma and examine how frequent overdiagnosis of melanoma is and whether this is related to different types of interventions or diagnostic technologies.

DESIGN AND SETTING

Empirical studies that discussed overdiagnosis in malignant melanoma were eligible, including qualitative and quantitative studies in any type of population, age group and geographical location. We excluded studies that did not include empirical data, studies that only mentioned 'overdiagnosis' without addressing it further and studies that used the term overdiagnosis for cases of misdiagnosis or false positives.We developed the search strategy in cooperation with an information specialist. We searched five databases on 21 April 2022: MEDLINE, Embase, CINAHL, PsycINFO and Cochrane Library.This scoping review adheres to The JBI methodology and Prefered Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping reviews (PRISMA-ScR). Two reviewers independently screened titles, abstracts and full texts for inclusion and extracted data from the included studies. The data extracted include study characteristics, population details, research question, the context and the study's main results.

RESULTS

Our search resulted in 1134 potentially relevant studies. 35 studies were included: 29 register studies, 3 cohort studies, 1 case-control study, 1 survey study and 1 randomised controlled trial. Most register studies examined trends in melanoma incidence and/or mortality and found a significant increase in incidence between 0.39% and 6.6% annually and a little or no increase in mortality. Three cohort studies and one case-control study showed that skin screening was associated with increased detection of melanoma; especially in situ or thin invasive melanoma. Three studies estimated the degree of overdiagnosis which ranged from 29% to 60%.

CONCLUSIONS

Epidemiological data suggest a high degree of overdiagnosis in malignant melanoma. Studies that examined the association between skin screening and malignant melanoma all found increased detection of melanomas, mostly thin and in situ melanomas, which raises concern about overdiagnosis.

Barriers and facilitators to sustainable operating theatres: a systematic review using the Theoretical Domains Framework

BACKGROUND

The health sector contributes significantly to the climate crisis. Operating theatres (OTs) in particular are a major contributor of greenhouse gas emissions and waste, and while there are several evidence-based guidelines to reduce this impact, these are often not followed. The authors systematically reviewed the literature to identify barriers and facilitators of sustainable behaviour in OTs, categorising these using the Theoretical Domains Framework (TDF).

MATERIALS AND METHODS

Medline, Embase, PsychInfo, and Global Health databases were searched for articles published between January 2000 and June 2023, using the concepts: barriers and facilitators, sustainability, and surgery. Two reviewers screened abstracts from identified studies, evaluated quality, and extracted data. Identified determinants were mapped to TDF domains and further themes as required. The results were reported in line with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) and AMSTAR (A MeaSurement Tool to Assess Systematic Reviews) guidelines.

RESULTS

Twenty-one studies were selected for analysis and assessment (17 surveys and four interview studies) comprising 8286 participants, including surgeons, nurses, and anaesthetists. Eighteen themes across 10 TDF domains were identified. The most common barriers to adoption of green behaviours in OTs were in domains of: 'knowledge' ( N =18), for example knowledge of sustainable practices; 'environmental context and resources' ( N =16) for example personnel shortage and workload and inadequate recycling facilities; 'social influences' ( N =9) for example lack of leadership/organisational mandate or support; 'beliefs about consequences' ( N =9) for example concerns regarding safety. Intention was the most common facilitator, with 11 studies citing it.

CONCLUSIONS

Despite intentions to adopt sustainable practices in OTs, this review identified several barriers to doing so. Interventions should focus on mitigating these, especially by improving staff's knowledge of sustainability practices and working within the environmental context and time pressures. Furthermore, institutional change programmes and policies are needed to prioritise sustainability at the hospital and trust level. Additional qualitative work should also be conducted using behavioural frameworks, to more comprehensively investigate barriers and determinants to decarbonise OTs.

Choosing Wisely Italy, and the role of doctors in containing the climate emergency

The philosopher of science, Telmo Pievani, in his beautiful and passionate presentation on 30 September 2023, at the conclusion of the 60th National Congress of the Italian Association of Hospital Dermatologists (ADOI) held in Vicenza, reminded us with simple words and concrete examples of the devastating impact of human behavior on the environment and biodiversity, highlighting the growing deterioration of the delicate natural balances that preserve terrestrial ecosystems and with them life on our planet [...]

An EAACI review: Go green in health care and research. Practical suggestions for sustainability in clinical practice, laboratories, and scientific meetings

Health care professionals (HCPs) and researchers in the health care sector dedicate their professional life to maintaining and optimizing the health of their patients. To achieve this, significant amounts of resources are used and currently it is estimated that the health care sector contributes to more than 4% of net greenhouse gas (GHG) emissions. GHG emissions adversely impact planetary health and consequently human health, as the two are intricately linked. There are many factors of health care that contribute to these emissions. Hospitals and research labs also use high amounts of consumables which require large amounts of raw materials and energy to produce. They are further responsible for polluting the environment via disposal of plastics, drug products, and other chemicals. To maintain and develop state-of-the-art best practices and treatments, medical experts exchange and update their knowledge on methods and technologies in the respective fields at highly specialized scientific meetings. These meetings necessitate thousands of attendants traveling around the globe. Therefore, while the goal of HCPs is to care for the individual, current practices have an enormous (indirect) impact on the health of the patients by their negative environmental impacts. There is an urgent need for HCPs and researchers to mitigate these detrimental effects. The installation of a sustainability-manager at health care facilities and research organizations to implement sustainable practices while still providing quality health care is desirable. Increased use of telemedicine, virtual/hybrid conferences and green chemistry have recently been observed. The benefits of these practices need to be evaluated and implemented as appropriate. With this manuscript, we aim to increase the awareness about the negative impacts of the health care system (including health care research) on planetary and human health. We suggest some easy and highly impactful steps and encourage health care professionals and research scientists of all hierarchical levels to immediately implement them in their professional as well as private life to counteract the health care sector's detrimental effects on the environment.

Improving environmental sustainability of intensive care units: A mini-review

The carbon footprint of healthcare is significantly impacted by intensive care units, which has implications for climate change and planetary health. Considering this, it is crucial to implement widespread efforts to promote environmental sustainability in these units. A literature search for publications relevant to environmental sustainability of intensive care units was done using PubMed. This mini-review seeks to equip intensive care unit practitioners and managers with the knowledge necessary to measure and mitigate the carbon cost of healthcare for critically ill patients. It will also provide an overview of the current progress in this field and its future direction.

Reductions in inhaler greenhouse gas emissions by addressing care gaps in asthma and chronic obstructive pulmonary disease: an analysis

INTRODUCTION

Climate change from greenhouse gas (GHG) emissions represents one of the greatest public health threats of our time. Inhalers (and particularly metred-dose inhalers (MDIs)) used for asthma and chronic obstructive pulmonary disease (COPD), constitute an important source of GHGs. In this analysis, we aimed to estimate the carbon footprint impact of improving three distinct aspects of respiratory care that drive avoidable inhaler use in Canada.

METHODS

We used published data to estimate the prevalence of misdiagnosed disease, existing inhaler use patterns, medication class distributions, inhaler type distributions and GHGs associated with inhaler actuations, to quantify annual GHG emissions in Canada: (1) attributable to asthma and COPD misdiagnosis; (2) attributable to overuse of rescue inhalers due to suboptimally controlled symptoms; and (3) avoidable by switching 25% of patients with existing asthma and COPD to an otherwise comparable therapeutic option with a lower GHG footprint.

RESULTS

We identified the following avoidable annual GHG emissions: (1) ~49 100 GHG metric tons (MTs) due to misdiagnosed disease; (2) ~143 000 GHG MTs due to suboptimal symptom control; and (3) ~262 100 GHG MTs due to preferential prescription of strategies featuring MDIs over lower-GHG-emitting options (when 25% of patients are switched to lower GHG alternatives). Combined, the GHG emission reductions from bridging these gaps would be the equivalent to taking ~101 100 vehicles off the roads each year.

CONCLUSIONS

Our analysis shows that the carbon savings from addressing misdiagnosis and suboptimal disease control are comparable to those achievable by switching one in four patients to lower GHG-emitting therapeutic strategies. Behaviour change strategies required to achieve and sustain delivery of evidence-based real-world care are complex, but the added identified incentive of carbon footprint reduction may in itself prove to be a powerful motivator for change among providers and patients. This additional benefit can be leveraged in future behaviour change interventions.

A Review of the Applicability of Current Green Practices in Healthcare Facilities

BACKGROUND

Circular economy (CE) has raised great interest as a concept and as a development model worldwide. This concept aims to provide a substitute for the linear economic model, which was based on production and consumption, continuous growth, and resources depletion. CE allows a greener economy with sustainable development and promotes more balanced societies. The healthcare sector is a major contributor to the climate crisis, with a carbon footprint representing 4.4% of global net emissions. It is thus essential to rethink the applicability of CE in healthcare.

METHODS

We conducted a scoping review guided by the Arksey and O'Malley methodological framework and utilised PRISMA-ScR (Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews) checklist. A systematic search from MEDLINE complete, SCOPUS, and Web of Science databases published between 1992 and 2022.

RESULTS

Through database searching a total of 1018 records were identified and 475 duplicates were removed. From the total search, 543 articles were screened by title/abstract according to the inclusion and exclusion criteria. After screening, 38 full-text articles were selected and assessed for eligibility. Forty-seven additional records were also identified through other sources and screened for eligibility. Other sources included: 12 articles from snowballing of previous papers; 9 articles following peer-reviewers suggestions; 19 reports from relevant organisations in CE and healthcare; two webpage, and one book.

CONCLUSION

Specific areas were identified where hospitals could reduce their greenhouse gas (GHG) emissions and consequently their negative environmental impact, namely through waste management, energy, water, transportation/travel, hospital design, food optimisation, green procurement, and behaviour. Also, lack of staff awareness and knowledge of the environmental impact of healthcare, and hospitals sustainability were identified as major contributors.

Anaesthesia and environment: impact of a green anaesthesia on economics

The excessive growth of the health sector has created an industry that, while promoting health, is now itself responsible for a significant part of global environmental pollution. The health crisis caused by climate change urges us to transform healthcare into a sustainable industry. This review aims to raise awareness about this issue and to provide practical and evidence-based recommendations for anaesthesiologists.

Sustainable development in general practice

BACKGROUND

As health care accounts for 4-5% of global carbon emissions, many health organisations have called for implementing sustainable development actions in health care. However, sustainable development measures in general practice are rarely implemented by physicians. The aim of this study was to explore the practices of general practitioners (GPs) in terms of sustainable development to identify which actions are appropriate and achievable.

METHODS

A qualitative study was conducted in 12 French GPs using face-to-face or telephone interviews, transcribed verbatim and analysed through a global inductive analysis with constant comparison. Semi-structured interviews were focussed on waste management, relationships between health professionals, sustainable development, and GPs' activity.

RESULTS

The mean age of the GPs was 42.8 years and they mainly worked in an urban environment. The interviews highlighted 4 themes. It appeared that a balance needs to be found between the environmental impact and the constraints related to medical care. To be able to think about integrating sustainable development into health care, GPs should make a personal commitment to change their routine. In practice, consumption should be reassessed, prescriptions and prevention reconsidered. These actions could be applied to the GPs' environment as role models for their patients, business leaders, and members of the healthcare system.

CONCLUSION

GPs felt concerned by sustainable development and were already involved in its implementation in their practice. Tools are available to help GPs to continue to implement their actions described in this article, but their impact remains to be investigated.

Incorporating 'Green Podiatry' into your clinic, and into your life

BACKGROUND

This commentary outlines practical ways of positively incorporating green podiatry, foot health, physical activity benefits, and relevance to climate change into the clinical setting as Conference of Parties (COP27) approaches. Recent reports from the Intergovernmental Panel on Climate Change, the World Economic Forum, and undergraduate curricula concerns, are presented.

MAIN BODY

Climate change is irrefutable, and as health professionals, podiatrists can discuss the benefits and principles of green podiatry with patients of all ages in their clinics, appreciating that people are increasingly worried about the climate crisis. Feet as fundamental for independent, healthy, and carbon-neutral active transport, needs to become a key message. The three pillars for green podiatry are exercise, evidence, and the everyday changes that all podiatrists can make. Likewise, podiatrists can encourage their patients, and in doing so, join with community leadership, alongside other allied health and medical peers.

CONCLUSION

Podiatrists have a shared responsibility to work and live as 'green' as possible, and to share this message with patients. Reducing waste, physically and in the form of unnecessary treatment, and supporting a review of supply chains, are important aspects of reducing health care emissions. Promoting feet as carbon-neutral transport, and physical activity as evidence based and health enhancing, are a sound contribution to twenty-first century public health. Podiatry has a great opportunity for positive legacy.

Melanoma overdiagnosis: why it matters and what can be done about it

Linked Article:Whiteman et al. Br J Dermatol 2022; 187:515–522.

Health, financial and environmental impacts of unnecessary vitamin D testing: a triple bottom line assessment adapted for healthcare

OBJECTIVE

To undertake an assessment of the health, financial and environmental impacts of a well-recognised example of low-value care; inappropriate vitamin D testing.

DESIGN

Combination of systematic literature search, analysis of routinely collected healthcare data and environmental analysis.

SETTING

Australian healthcare system.

PARTICIPANTS

Population of Australia.

OUTCOME MEASURES

We took a sustainability approach, measuring the health, financial and environmental impacts of a specific healthcare activity. Unnecessary vitamin D testing rates were estimated from best available published literature; by definition, these provide no gain in health outcomes (in contrast to appropriate/necessary tests). Australian population-based test numbers and healthcare costs were obtained from Medicare for vitamin D pathology services. Carbon emissions in kg CO2e were estimated using data from our previous study of the carbon footprint of common pathology tests. We distinguished between tests ordered as the primary test and those ordered as an add-on to other tests, as many may be done in conjunction with other tests. We conducted base case (8% being the primary reason for the blood test) and sensitivity (12% primary test) analyses.

RESULTS

There were a total of 4 457 657 Medicare-funded vitamin D tests in 2020, on average one test for every six Australians, an 11.8% increase from the mean 2018-2019 total. From our literature review, 76.5% of Australia's vitamin D tests provide no net health benefit, equating to 3 410 108 unnecessary tests in 2020. Total costs of unnecessary tests to Medicare amounted to >$A87 000 000. The 2020 carbon footprint of unnecessary vitamin D tests was 28 576 kg (base case) and 42 012 kg (sensitivity) CO2e, equivalent to driving ~160 000-230 000 km in a standard passenger car.

CONCLUSIONS

Unnecessary vitamin D testing contributes to avoidable CO2e emissions and healthcare costs. While the footprint of this example is relatively small, the potential to realise environmental cobenefits by reducing low-value care more broadly is significant.

We can't mitigate what we don't monitor: using informatics to measure and improve healthcare systems' climate impact and environmental footprint

Climate change, human health, and healthcare systems are inextricably linked. As the climate warms due to greenhouse gas (GHG) emissions, extreme weather events, such as floods, fires, and heatwaves, will drive up demand for healthcare. Delivering healthcare also contributes to climate change, accounting for ∼5% of the global carbon emissions. To rein in healthcare's carbon footprint, clinicians and health policy makers must be able to measure the GHG contributions of healthcare systems and clinical practices. Herein, we scope potential informatics solutions to monitor the carbon footprint of healthcare systems and to support climate-change decision-making for clinicians, and healthcare policy makers. We discuss the importance of methods and tools that can link environmental, economic, and healthcare data, and outline challenges to the sustainability of monitoring efforts. A greater understanding of these connections will only be possible through further development and usage of models and tools that integrate diverse data sources.

The Carbon Footprint of Single-Use Flexible Cystoscopes compared to Reusable Cystoscopes

INTRODUCTION

Single-use devices for endourological procedures are becoming more popular. The environmental impact of single-use instruments is relatively unknown. This study aimed to compare the carbon footprint of single-use versus reusable flexible cystoscopes based on waste production and estimated carbon emissions.

METHODS

An analysis of the solid waste produced when using the aScope™ 4Cysto (Ambu®) single-use flexible cystoscope compared to the reusable Cysto-Nephro Videoscope CYF-VA2 (Olympus®) was performed. The solid waste generated was measured (grams) and recorded as either recyclable, landfill or contaminated, and CO2 produced by disposal, manufacture and cleaning was calculated.

RESULTS

40 flexible cystoscopies (20 single-use and 20 reusable) were analysed. Median total weight of waste produced was 622g (IQR621-651) for the single-use cystoscope compared to 671.5g (IQR659-677.5) for the reusable cystoscope (p<0.0001). More waste was disposed of by incineration after single-use than reusable cystoscopy (496g [IQR495-525] vs 415g [IQR403-421.5], p<0.0001). However, more waste went to landfill after reusable cystoscopy (256g±0 vs 126g±0, p<0.0001). There was no difference in weight of waste produced based on the indication for cystoscopy (p=0.1570). A total of 2.41kg of CO2 (IQR 2.40-2.44) was produced per case for the single-use flexible cystoscope compared with 4.23kg of CO2 (IQR 4.22-4.24) for the reusable cystoscope (p<0.0001).

CONCLUSION

Environmental accountability is essential in modern healthcare. This study highlights that disposable flexible cystoscopes have a significantly lower impact on the environment in terms of carbon footprint and landfill. We propose that environmental impact studies should be a routine part of device development for a sustainable future.

A novel methodological framework was described for detecting and quantifying overdiagnosis

OBJECTIVES

Methods to quantify overdiagnosis of screen detected cancer have been developed, but methods for quantifying overdiagnosis of non-cancer conditions (whether symptomatic or asymptomatic) have been lacking. We aimed to develop a methodological framework for quantifying overdiagnosis that may be used for asymptomatic or symptomatic conditions, and used Gestational Diabetes Mellitus as an example of how it may be applied.

STUDY DESIGN AND SETTING

We identify two earlier definitions for overdiagnosis, a narrower prognosis-based definition, and a wider utility-based definition. Building on the central importance of the concepts of prognostic information and clinical utility of a diagnosis, we consider the following questions: within a target population, do people found to have a disease using one diagnostic strategy but found not to have the disease using another diagnostic strategy (so called 'additional diagnoses'), have an increased risk of adverse clinical outcomes without treatment (prognosis evidence), and/or a decreased risk of adverse outcomes with treatment (utility evidence)?

RESULTS

Using Causal Directed Acyclic Graphs and Fair Umpires, we illuminate the relationships between diagnostics strategies and the frequency of overdiagnosis. We then use the example of Gestational Diabetes Mellitus to demonstrate how the Fair Umpire framework may be applied to estimate overdiagnosis.

CONCLUSION

Our framework may be used to quantify overdiagnosis in non-cancer conditions (and in cancer conditions), as well as to guide further studies on this topic.