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Building back better children's surgical services toward universal health coverage: Perspectives from Bangladesh and Zimbabwe.

INTRODUCTION: This article is part of the Research Topic 'Health Systems Recovery in the Context of COVID-19 and Protracted Conflict'. Children's surgical services are crucial, yet underappreciated, for children's health and must be sufficiently addressed to make and sustain progress toward universal health coverage (UHC). Despite their considerable burden and socioeconomic cost, surgical diseases have been relatively neglected in favor of communicable diseases living up to their inauspicious moniker: 'the neglected stepchild of global health'. This article aims to raise awareness around children's surgical diseases and offers perspectives from two prototypical LMICs on strengthening surgical services in the context of health systems recovery following the COVID-19 experience to make and sustain progress toward UHC. APPROACH: We used a focused literature review supplemented by the perspectives of local experts and the 6-components framework for surgical systems planning to present two case studies of Bangladesh and Zimbabwe. The lived experiences of the authors are used to describe the impact of COVID-19 on respective surgical systems and offer perspectives on building back the health system and recovering essential health services for sustainability and resilience. FINDINGS: We found that limited high-level policy and planning instruments, an overburdened and under-resourced health and allied workforce, underdeveloped surgical infrastructure (from key utilities to essential medical products), lack of locally generated research, and the specter of prohibitively high out-of-pocket costs for children's surgery are common challenges in both countries that have been exacerbated by the COVID-19 pandemic. DISCUSSION: Continued chronic underinvestment and inattention to children's surgical diseases coupled with the devastating effect of the COVID-19 pandemic threaten progress toward key global health objectives. Urgent attention and investment in the context of health systems recovery is needed from policy to practice levels to improve infrastructure; attract, retain and train the surgical and allied health workforce; and improve service delivery access with equity considerations to meet the 2030 Lancet Commission goals, and make and sustain progress toward UHC and the SDGs.

Exploring the Impact of COVID-19 on Progress Towards Achieving Global Surgery Goals.

INTRODUCTION: In the 5 months since it began, the COVID-19 pandemic has placed extraordinary demands on health systems around the world including surgery. Competing health objectives and resource redeployment threaten to retard the scale-up of surgical services in low- and middle-income countries where access to safe, affordable and timely care is low. The key aspiration of the Lancet Commission on global surgery was promotion of resilience in surgical systems. The current pandemic provides an opportunity to stress-test those systems and identify fault-lines that may not be easily apparent outside of times of crisis. METHODS: We endeavoured to explore vulnerable points in surgical systems learning from the experience of past outbreaks, using examples from the current pandemic, and make recommendations for future health emergencies. The 6-component framework for surgical systems planning was used to categorise the effects of COVID-19 on surgical systems, with a particular focus on low- and middle-income countries. Key vulnerabilities were identified and recommendations were made for the current pandemic and for the future. RESULTS: Multiple stress points were identified throughout all of the 6 components of surgical systems. The impact is expected to be highest in the workforce, service delivery and infrastructure domains. Innovative new technologies should be employed to allow consistent, high-quality surgical care to continue even in times of crisis. CONCLUSIONS: If robust progress towards global surgery goals for 2030 is to continue, the stress points identified should be reinforced. An ongoing process of reappraisal and fortification will keep surgical systems in low- and middle-income countries responsive to "old threats and new challenges". Multiple opportunities exist to help realise the dream of surgical systems resilient to external shocks.

Anorectal malformations in low and middle-income countries- spectrum, burden and management.

The clinical presentation, diagnosis and management of anorectal malformation has been well described in the literature, however the experience with these conditions in low-and middle-income countries is often shaped in unique ways due to the social, cultural and economic factors at work in these regions. This leads to adaptation of modifications in management options for these babies that usually present as delayed cases with added poor prognostic factors like sepsis leading to need for emergency resuscitation and overall increased morbidity and mortality. This article explores the anomaly from a global surgery lens and outlines the spectrum of the anomaly, burden faced in the resource constrained environment and the management options adopted for successful management under the available circumstances.

The impact of the COVID-19 pandemic on paediatric surgical volumes in Africa: A retrospective observational study.

BACKGROUND: The aim of this study is to investigate the impact that COVID-19 had on the pattern and trend of surgical volumes, urgency and reason for surgery during the first 6 months of the pandemic in sub-Saharan Africa. METHODS: This retrospective facility-based study involved collection of paediatric operation data from operating theatre records across 5 hospitals from 3 countries: Zimbabwe, Zambia and Nigeria over the first half of 2019 and 2020 for comparison. Data concerning diagnosis, procedure, anaesthesia, grade, speciality, NCEPOD classification and indication was collected. The respective dates of enactment of cancellation policies in each country were used to compare changes in weekly median surgical case volume before cancellation using the Wilcoxon Sign-Rank Test. RESULTS: A total of 1821 procedures were recorded over the study period. Surgical volumes experienced a precipitous drop overall from a median of 100 cases/week to 50 cases/week coinciding with cancellation of surgical electives. Median accumulated weekly procedures before COVID-related cancellation were significantly different from those after cancellation (p = 0.027). Emergency surgery fell by 23.3% while electives fell by 78,9% (P = 0.042). The most common primary indication for surgery was injury which experienced a 30.5% drop in number of procedures, only exceeded by congenital surgery which dropped 34.7%. CONCLUSIONS: The effects of surgical cancellations during the covid-19 pandemic are particularly devastating in African countries where the unmet need and surgical caseload are high. Continued cancellations that have since occurred will cause similar drops in surgical case volume that these health systems may not have the resilience to recover from. LEVEL OF EVIDENCE: Level II.

Favourable perioperative outcomes for children with SARS-CoV-2.

Mitigating the impact of COVID-19 on children's surgery in Africa.

Safety of Robotic cholecystectomy as index training procedure - the UK experience

The impact of the COVID-19 pandemic upon pancreatic cancer treatment (CONTACT Study): a UK national observational cohort study.

INTRODUCTION: CONTACT is a national multidisciplinary study assessing the impact of the COVID-19 pandemic upon diagnostic and treatment pathways among patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: The treatment of consecutive patients with newly diagnosed PDAC from a pre-COVID-19 pandemic cohort (07/01/2019-03/03/2019) were compared to a cohort diagnosed during the first wave of the UK pandemic ('COVID' cohort, 16/03/2020-10/05/2020), with 12-month follow-up. RESULTS: Among 984 patients (pre-COVID: n = 483, COVID: n = 501), the COVID cohort was less likely to receive staging investigations other than CT scanning (29.5% vs. 37.2%, p = 0.010). Among patients treated with curative intent, there was a reduction in the proportion of patients recommended surgery (54.5% vs. 76.6%, p = 0.001) and increase in the proportion recommended upfront chemotherapy (45.5% vs. 23.4%, p = 0.002). Among patients on a non-curative pathway, fewer patients were recommended (47.4% vs. 57.3%, p = 0.004) or received palliative anti-cancer therapy (20.5% vs. 26.5%, p = 0.045). Ultimately, fewer patients in the COVID cohort underwent surgical resection (6.4% vs. 9.3%, p = 0.036), whilst more patients received no anti-cancer treatment (69.3% vs. 59.2% p = 0.009). Despite these differences, there was no difference in median overall survival between the COVID and pre-COVID cohorts, (3.5 (IQR 2.8-4.1) vs. 4.4 (IQR 3.6-5.2) months, p = 0.093). CONCLUSION: Pathways for patients with PDAC were significantly disrupted during the first wave of the COVID-19 pandemic, with fewer patients receiving standard treatments. However, no significant impact on survival was discerned.

Safety of robotic cholecystectomy as index training procedure: the UK experience.

AIMS: To evaluate the safety profile of robotic cholecystectomy performed within the United Kingdom (UK) Robotic Hepatopancreatobiliary (HPB) training programme. METHODS: A retrospective evaluation of prospectively collected data from eleven centres participating in the UK Robotic HPB training programme was conducted. All adult patients undergoing robotic cholecystectomy for symptomatic gallstone disease or gallbladder polyp were considered. Bile duct injury, conversion to open procedure, conversion to subtotal cholecystectomy, length of hospital stay, 30-day re-admission, and post-operative complications were the evaluated outcome parameters. RESULTS: A total of 600 patients were included. The median age was 53 (IQR 65-41) years and the majority (72.7%; 436/600) were female. The main indications for robotic cholecystectomy were biliary colic (55.5%, 333/600), cholecystitis (18.8%, 113/600), gallbladder polyps (7.7%, 46/600), and pancreatitis (6.2%, 37/600). The median length of stay was 0 (IQR 0-1) days. Of the included patients, 88.5% (531/600) were discharged on the day of procedure with 30-day re-admission rate of 5.5% (33/600). There were no bile duct injuries and the rate of conversion to open was 0.8% (5/600) with subtotal cholecystectomy rate of 0.8% (5/600). CONCLUSION: The current study confirms that robotic cholecystectomy can be safely implemented to routine practice with a low risk of bile duct injury, low bile leak rate, low conversion to open surgery, and low need for subtotal cholecystectomy.

Simultaneous versus delayed resection of synchronous colorectal liver metastases: A systematic review and meta-analysis.

Colorectal cancer is a leading malignancy, with synchronous colorectal liver metastases (CRLM) presenting in 20 % of patients. Resection remains the gold standard treatment for CRLMs, significantly improving survival outcomes. However, the optimal timing of resection of these synchronous lesions - simultaneous versus staged - remains controversial. This systematic review and meta-analysis synthesises data exclusively from propensity-score-matched and prospective studies. A comprehensive search of five databases identified 11 eligible studies, encompassing 2884 patients. Of these, 1453 underwent simultaneous resection, and 1431 underwent staged procedures. The primary outcome was 5-year overall survival (OS), with secondary outcomes including disease-free survival (DFS), surgical morbidity, operating time, and length of hospital stay. Meta-analysis demonstrated no significant difference in 5-year OS between simultaneous and staged resection groups (odds ratio [OR] 1.10, 95 % CI 0.75-1.61; p = 0.83). However, simultaneous resection was associated with significantly higher 3-year DFS (OR 1.67, 95 % CI 1.28-2.17; p = 0.0001) but also increased major surgical complications (Clavien-Dindo ≥ III: OR 1.32, 95 % CI 1.03-1.68; p = 0.03). This review highlights a lack of oncological advantage for simultaneous resection, coupled with higher morbidity, suggesting its use should be limited to select patients with low surgical risk. The findings underscore the need for well-powered, randomised trials to confirm these conclusions, as well as assess quality of life and economic outcomes, however delivering such trials in this patient cohort brings unique challenges. Until such data are available, clinical decision-making should remain individualised, guided by multidisciplinary discussion and available local expertise.

A systematic review and meta-analysis of operative versus non-operative management for first time traumatic anterior shoulder dislocation in young adults.

BACKGROUND: The most appropriate management following primary traumatic anterior shoulder dislocation in young adults is unclear. This systematic review and meta-analysis evaluated operative versus non-operative management. The primary outcome measure was re-dislocation rate, in contrast to the often reported 'recurrent instability', which includes subjective instability. METHODS: Our review was prospectively registered with PROSPERO (CRD42022322600) and reported as per PRISMA guidelines. Selection criteria included mean age of participants between 15 and 25 and minimum follow-up of 1 year. RESULTS: 21 studies meet the inclusion criteria with 5142 patients included. The mean age of patients was 23, with 87% male. There was a median of 54 patients per study and a mean follow up of 46 months per study. The mean re-dislocation rate was 16.08% in the operative group and 24.84% in the non-operative group. In the subgroup meta-analysis, including only RCTs, comparing arthroscopic stabilisation vs non-operative there was an odds ratio of 0.09, strongly favouring intervention. DISCUSSION: This systematic review found the literature available supports surgical intervention in patients under the age of 25, in order to reduce re-dislocation. However, there is a lack of cost-effectiveness data to support these findings, and this should be an area of future research.

Loss of tetraspanin-7 expression reduces pancreatic β-cell exocytosis Ca2+ sensitivity but has limited effect on systemic metabolism.

BACKGROUND: Tetraspanin-7 (Tspan7) is an islet autoantigen involved in autoimmune type 1 diabetes and known to regulate β-cell L-type Ca2+ channel activity. However, the role of Tspan7 in pancreatic β-cell function is not yet fully understood. METHODS: Histological analyses were conducted using immunostaining. Whole-body metabolism was tested using glucose tolerance test. Islet hormone secretion was quantified using static batch incubation or dynamic perifusion. β-cell transmembrane currents, electrical activity and exocytosis were measured using whole-cell patch-clamping and capacitance measurements. Gene expression was studied using mRNA-sequencing and quantitative PCR. RESULTS: Tspan7 is expressed in insulin-containing granules of pancreatic β-cells and glucagon-producing α-cells. Tspan7 knockout mice (Tspan7y/- mouse) exhibit reduced body weight and ad libitum plasma glucose but normal glucose tolerance. Tspan7y/- islets have normal insulin content and glucose- or tolbutamide-stimulated insulin secretion. Depolarisation-triggered Ca2+ current was enhanced in Tspan7y/- β-cells, but β-cell electrical activity and depolarisation-evoked exocytosis were unchanged suggesting that exocytosis was less sensitive to Ca2+ . TSPAN7 knockdown (KD) in human pseudo-islets led to a significant reduction in insulin secretion stimulated by 20 mM K+ . Transcriptomic analyses show that TSPAN7 KD in human pseudo-islets correlated with changes in genes involved in hormone secretion, apoptosis and ER stress. Consistent with rodent β-cells, exocytotic Ca2+ sensitivity was reduced in a human β-cell line (EndoC-βH1) following Tspan7 KD. CONCLUSION: Tspan7 is involved in the regulation of Ca2+ -dependent exocytosis in β-cells. Its function is more significant in human β-cells than their rodent counterparts.

Divergent trajectories of antiviral memory after SARS-CoV-2 infection.

The trajectories of acquired immunity to severe acute respiratory syndrome coronavirus 2 infection are not fully understood. We present a detailed longitudinal cohort study of UK healthcare workers prior to vaccination, presenting April-June 2020 with asymptomatic or symptomatic infection. Here we show a highly variable range of responses, some of which (T cell interferon-gamma ELISpot, N-specific antibody) wane over time, while others (spike-specific antibody, B cell memory ELISpot) are stable. We use integrative analysis and a machine-learning approach (SIMON - Sequential Iterative Modeling OverNight) to explore this heterogeneity. We identify a subgroup of participants with higher antibody responses and interferon-gamma ELISpot T cell responses, and a robust trajectory for longer term immunity associates with higher levels of neutralising antibodies against the infecting (Victoria) strain and also against variants B.1.1.7 (alpha) and B.1.351 (beta). These variable trajectories following early priming may define subsequent protection from severe disease from novel variants.

A Safety Evaluation of the Resumption of Elective Orthopaedic Services in Higher Risk Patients During the COVID-19 Pandemic.

Introduction The COVID-19 pandemic has caused mass disruption to all aspects of society, with elective orthopaedics not spared. The pandemic has the potential to cause a tsunami of health burden in the community if elective services are not resumed to pre-pandemic levels of activity. Studies have shown that elective orthopaedics can be safely carried out in a COVID-19 free hospital. This study reviewed the transition in operating at an independent COVID-19 free hospital to an NHS hospital concurrently treating patients with COVID-19. Methods A strategy of phased relaxation of clinical comorbidity criteria was followed. Patients from the orthopaedic waiting list were selected according to these criteria and observed recommended preoperative isolation protocols. Operations were undertaken in the independent sector under the COVID-19 contract and the NHS site. Patients were assessed from all phases in the resumption of services. In-hospital and post-operative complications with specific enquiries regarding the development of COVID-19 symptoms or the need and outcome for COVID-19 testing at 14 days and six weeks was recorded. Results This study included 263 patients, of which 155 were female. The mean age of patients was 52.45. The mean BMI of all patients was 29.1 kg/m2. Additionally, 124 patients were American Society of Anesthesiologists (ASA) grade 1, 117 ASA grade 2 and 22 ASA grade 3 and 167 patients underwent a major operation, with total hip replacement being the most common operation. There were no in-hospital complications. No patients had a positive test result or symptoms of COVID-19 in the six-week post-operative period. Conclusion In summary, we demonstrated that elective orthopaedic surgery can be safely undertaken via a green pathway in a higher risk patient cohort when COVID-19 is prevalent in the community.

T-cell and antibody responses to first BNT162b2 vaccine dose in previously infected and SARS-CoV-2-naive UK health-care workers: a multicentre prospective cohort study

Background: Previous infection with SARS-CoV-2 affects the immune response to the first dose of the SARS-CoV-2 vaccine. We aimed to compare SARS-CoV-2-specific T-cell and antibody responses in health-care workers with and without previous SARS-CoV-2 infection following a single dose of the BNT162b2 (tozinameran; Pfizer–BioNTech) mRNA vaccine. Methods: We sampled health-care workers enrolled in the PITCH study across four hospital sites in the UK (Oxford, Liverpool, Newcastle, and Sheffield). All health-care workers aged 18 years or older consenting to participate in this prospective cohort study were included, with no exclusion criteria applied. Blood samples were collected where possible before vaccination and 28 (±7) days following one or two doses (given 3–4 weeks apart) of the BNT162b2 vaccine. Previous infection was determined by a documented SARS-CoV-2-positive RT-PCR result or the presence of positive anti-SARS-CoV-2 nucleocapsid antibodies. We measured spike-specific IgG antibodies and quantified T-cell responses by interferon-γ enzyme-linked immunospot assay in all participants where samples were available at the time of analysis, comparing SARS-CoV-2-naive individuals to those with previous infection. Findings: Between Dec 9, 2020, and Feb 9, 2021, 119 SARS-CoV-2-naive and 145 previously infected health-care workers received one dose, and 25 SARS-CoV-2-naive health-care workers received two doses, of the BNT162b2 vaccine. In previously infected health-care workers, the median time from previous infection to vaccination was 268 days (IQR 232–285). At 28 days (IQR 27–33) after a single dose, the spike-specific T-cell response measured in fresh peripheral blood mononuclear cells (PBMCs) was higher in previously infected (n=76) than in infection-naive (n=45) health-care workers (median 284 [IQR 150–461] vs 55 [IQR 24–132] spot-forming units [SFUs] per 106 PBMCs; p<0·0001). With cryopreserved PBMCs, the T-cell response in previously infected individuals (n=52) after one vaccine dose was equivalent to that of infection-naive individuals (n=19) after receiving two vaccine doses (median 152 [IQR 119–275] vs 162 [104–258] SFUs/106 PBMCs; p=1·00). Anti-spike IgG antibody responses following a single dose in 142 previously infected health-care workers (median 270 373 [IQR 203 461–535 188] antibody units [AU] per mL) were higher than in 111 infection-naive health-care workers following one dose (35 001 [17 099–55 341] AU/mL; p<0·0001) and higher than in 25 infection-naive individuals given two doses (180 904 [108 221–242 467] AU/mL; p<0·0001). Interpretation: A single dose of the BNT162b2 vaccine is likely to provide greater protection against SARS-CoV-2 infection in individuals with previous SARS-CoV-2 infection, than in SARS-CoV-2-naive individuals, including against variants of concern. Future studies should determine the additional benefit of a second dose on the magnitude and durability of immune responses in individuals vaccinated following infection, alongside evaluation of the impact of extending the interval between vaccine doses. Funding: UK Department of Health and Social Care, and UK Coronavirus Immunology Consortium.

Real-world evaluation of AI driven COVID-19 triage for emergency admissions: External validation & operational assessment of lab-free and high-throughput screening solutions

Background: Uncertainty in patients’ COVID-19 status contributes to treatment delays, nosocomial transmission, and operational pressures in hospitals. However, typical turnaround time for laboratory PCR remains 12-24h and lateral flow testing (LFD) has limited sensitivity. We recently demonstrated that AI-driven triage (CURIAL-1.0) provides rapid COVID-19 screening using clinical data routinely available within 1h of arrival to hospital. Here we aimed to improve time-to-result, perform external & prospective validation, and deploy a novel lab-free screening tool in a UK emergency department. Methods: We eliminated weakly-informative predictors to improve generalisability and speed, developing CURIAL-Lab with vital signs and readily available blood tests (FBC, U&E, LFT, CRP) and CURIAL-Rapide with vital signs and FBC alone. Models were validated externally for emergency admissions to University Hospitals Birmingham, Bedfordshire Hospitals & Portsmouth Hospitals University NHS trusts, and prospectively at Oxford University Hospitals, by comparison to confirmatory nucleic acid testing. Next, we compared model performance with LFDs and evaluated a combined pathway triaging patients to COVID-19-suspected clinical areas where either model prediction or LFD results were positive. Lastly, we deployed CURIAL-Rapide alongside an approved point-of-care FBC analyser to provide lab-free COVID-19 screening at the John Radcliffe Hospital (Oxford, UK). Our primary improvement outcome was time-to-result. Findings: 72,223 patients met eligibility criteria across four validating hospital groups. CURIAL-Lab & CURIAL-Rapide performed consistently (AUROC range 0.858-0.881 & 0.836-0.854), achieving highest sensitivity at Portsmouth Hospitals (84.1% [Wilson’s 95% CIs 82.5-85.7] & 83.5% [81.8-85.1]) at specificities of 71.3% (70.9-71.8) and 63.6% (63.1-64.1). When combined with LFDs, models predictions improved triage sensitivity from 56.9% for LFDs alone to 85.6% with CURIAL-Lab (81.6-88.9; AUROC 0.925) and 88.2% with CURIAL-Rapide (84.4-91.1; AUROC 0.919), thereby reducing missed COVID-19 cases by 65% & 72%. In prospective deployment of CURIAL-Rapide, 520 patients were enrolled for point-of-care FBC analysis, of whom 436 received confirmatory PCR testing and 10 (2.3%) tested positive. Median time from arrival to CURIAL-Rapide result was 45:00min (32-64), 16:00min (26.3%) sooner than LFD (61:00min, 37-99; log-rank p<0.0001), and 6:52h (90.2%) sooner than PCR (7:37h, 6:05-15:39; p<0.0001). Classification performance was high, with sensitivity of 87.5% (52.9-97.8), specificity of 85.4% (81.3-88.7) and NPV 99.7% (98.2-99.9). CURIAL-Rapide correctly excluded infection for 58.5% of patients who were triaged by a physician to a ‘COVID-19-suspected’ area but went on to test negative by PCR. Impact: Our findings demonstrate the generalisability, performance and real-world operational benefits of AI driven screening for COVID-19 over standard-care in emergency departments. CURIAL-Rapide provides rapid, lab-free screening when used with near-patient FBC analysis, and can reduce the number of COVID-19- negative patients triaged to COVID-19-suspected areas.

Immunogenicity of standard and extended dosing intervals of BNT162b2 mRNA vaccine.

Extension of the interval between vaccine doses for the BNT162b2 mRNA vaccine was introduced in the United Kingdom to accelerate population coverage with a single dose. At this time, trial data were lacking, and we addressed this in a study of United Kingdom healthcare workers. The first vaccine dose induced protection from infection from the circulating alpha (B.1.1.7) variant over several weeks. In a substudy of 589 individuals, we show that this single dose induces severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibody (NAb) responses and a sustained B and T cell response to the spike protein. NAb levels were higher after the extended dosing interval (6-14 weeks) compared with the conventional 3- to 4-week regimen, accompanied by enrichment of CD4+ T cells expressing interleukin-2 (IL-2). Prior SARS-CoV-2 infection amplified and accelerated the response. These data on dynamic cellular and humoral responses indicate that extension of the dosing interval is an effective immunogenic protocol.

Two doses of SARS-CoV-2 vaccination induce robust immune responses to emerging SARS-CoV-2 variants of concern.

The extent to which immune responses to natural infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and immunization with vaccines protect against variants of concern (VOC) is of increasing importance. Accordingly, here we analyse antibodies and T cells of a recently vaccinated, UK cohort, alongside those recovering from natural infection in early 2020. We show that neutralization of the VOC compared to a reference isolate of the original circulating lineage, B, is reduced: more profoundly against B.1.351 than for B.1.1.7, and in responses to infection or a single dose of vaccine than to a second dose of vaccine. Importantly, high magnitude T cell responses are generated after two vaccine doses, with the majority of the T cell response directed against epitopes that are conserved between the prototype isolate B and the VOC. Vaccination is required to generate high potency immune responses to protect against these and other emergent variants.

External validity of randomized clinical trials in vascular surgery: systematic review of demographic factors of patients recruited to randomized clinical trials with comparison to the National Vascular Registry.

BACKGROUND: Evidence-based medicine relies on randomized clinical trials, which should represent the patients encountered in clinical practice. Characteristics of patients recruited to randomized clinical trials involving vascular index operations (carotid endarterectomy, abdominal aortic aneurysm repair, infrainguinal bypass and major lower limb amputations) were compared with those recorded in the National Vascular Registry across England and Wales. METHODS: MEDLINE, Embase, Web of Science, CENTRAL, clinicaltrials.gov and World Health Organization International Trials Registry Platform (CRD42021247905) were searched for randomized clinical trials involving the index operations. Demographic (age, sex, ethnicity) and clinical (co-morbidities, medications, body mass index, smoking, alcohol, cognition) data were extracted, by operation. Characteristics of operated on patients were extracted from publicly available National Vascular Registry reports (2014-2020). All findings are reported according to PRISMA guidelines. Rayyan.AI, Excel and GraphPad Prism were used for screening and analysis. RESULTS: A total of 307 randomized clinical trials (66 449 patients) were included and compared with National Vascular Registry data for 119 019 patients. Randomized clinical trial patients were younger across all operations; for carotid endarterectomy, bypass and major lower limb amputation randomized clinical trials, there were differences in female patient representation. Further comparisons were limited by the insufficient baseline data reporting across randomized clinical trials, though reporting improved over decades. National Vascular Registry reports lacked information on patient factors such as patient ethnicity or body mass index. CONCLUSIONS: There are significant differences in demographic and clinical factors between patients recruited to vascular surgery randomized clinical trials and the real-world National Vascular Registry vascular surgery patient population. Minimum reporting standards for baseline data should be defined to allow future randomized clinical trials to represent real-world patient populations and ensure the external validity of their results.

Pilot study on large language models for risk-of-bias assessments in systematic reviews: A(I) new type of bias?