Publications

Search or filter publications

Filter by type:

Filter by publication type

Filter by year:

to

Results

  • Showing results for:
  • Reset all filters

Search results

  • Journal article
    Modi HN, SIngh H, Orihuela-Espina F, Athanasiou T, Fiorentino F, Yang GZ, Darzi A, Leff DRet al., 2017,

    Temporal stress in the operating room: brain engagement promotes "coping" and disengagement prompts "choking"

    , Annals of Surgery, Vol: 267, Pages: 683-691, ISSN: 1528-1140

    Objective:To investigate the impact of time pressure (TP) on prefrontalactivation and technical performance in surgical residents during a laparo-scopic suturing task.Background:Neural mechanisms enabling surgeons to maintain perform-ance and cope with operative stressors are unclear. The prefrontal cortex(PFC) is implicated due to its role in attention, concentration, and perform-ance monitoring.Methods:A total of 33 residents [Postgraduate Year (PGY)1 – 2¼15,PGY3– 4¼8, and PGY5¼10] performed a laparoscopic suturing taskunder ‘‘self-paced’’ (SP) and ‘‘TP’’ conditions (TP¼maximum 2 minutes perknot). Subjective workload was quantified using the Surgical Task LoadIndex. PFC activation was inferred using optical neuroimaging. Technicalskill was assessed using progression scores (au), error scores (mm), leakvolumes (mL), and knot tensile strengths (N).Results:TP led to greater perceived workload amongst all residents (meanSurgical Task Load Index score SD: PGY1 – 2: SP¼160.3 24.8 vs TP¼202.1 45.4,P<0.001; PGY3 – 4: SP¼123.0 52.0 vs TP¼172.5 43.1,P<0.01; PGY5: SP¼105.8 55.3 vs TP¼159.1 63.1,P<0.05).Amongst PGY1– 2 and PGY3– 4, deterioration in task progression, errorscores and knot tensile strength (P<0.05), and diminished PFC activationwas observed under TP. In PGY5, TP resulted in inferior task progression anderror scores (P<0.05), but preservation of knot tensile strength. Furthermore,PGY5 exhibited less attenuation of PFC activation under TP, and greateractivation than either PGY1 – 2 or PGY3 – 4 under both experimental con-ditions (P<0.05).Conclusions:Senior residents cope better with temporal demands and exhibitgreater technical performance stability under pressure, possibly due to
  • Journal article
    Kulasabanathan K, Issa H, Bhatti Y, Prime M, del Castillo J, Darzi A, Harris Met al., 2017,

    Do international health partnerships contribute to reverse innovation? A mixed methods study of THET-supported partnerships in the UK

    , Globalization and Health, Vol: 13, ISSN: 1744-8603

    BackgroundInternational health partnerships (IHPs) are changing, with an increased emphasis on mutual accountability and joint agenda setting for both the high- and the low- or middle-income country (LMIC) partners. There is now an important focus on the bi-directionality of learning however for the UK partners, this typically focuses on learning at the individual level, through personal and professional development. We sought to evaluate whether this learning also takes the shape of ‘Reverse Innovation’ –when an idea conceived in a low-income country is subsequently adopted in a higher-income country.MethodsThis mixed methods study used an initial scoping survey of all the UK-leads of the Tropical Health Education Trust (THET)-supported International Health Partnerships (n = 114) to ascertain the extent to which the IHPs are or have been vehicles for Reverse Innovation. The survey formed the sampling frame for further deep-dive interviews to focus on volunteers’ experiences and attitudes to learning from LMICs. Interviews of IHP leads (n = 12) were audio-recorded and transcribed verbatim. Survey data was analysed descriptively. Interview transcripts were coded thematically, using an inductive approach.ResultsSurvey response rate was 27% (n = 34). The majority (70%) strongly agreed that supporting LMIC partners best described the mission of the partnership but only 13% of respondents strongly agreed that learning about new innovations and models was a primary mission of their partnership. Although more than half of respondents reported having observed innovative practice in the LMIC, only one IHP respondent indicated that this has led to Reverse Innovation. Interviews with a sample of survey respondents revealed themes primarily around how learning is conceptualised, but also a central power imbalance between the UK and LMIC partners. Paternalistic notions of knowledge could be traced to partnership p
  • Journal article
    Ramdas K, Darzi A, 2017,

    Adopting Innovations in Care Delivery - The Case of Shared Medical Appointments

    , NEW ENGLAND JOURNAL OF MEDICINE, Vol: 376, Pages: 1105-1107, ISSN: 0028-4793
  • Book chapter
    Hassen Y, Johnston M, Barrow EJ, Darzi Aet al., 2017,

    Safety and the Use of Checklists in Acute Care Surgery

    , Acute Care Surgery Handbook Volume 1 General Aspects, Non-gastrointestinaI and Critical Care Emergencies, Publisher: Springer, ISBN: 9783319153407

    This pocket manual is a practically oriented, wide-ranging guide to acute care surgery general aspects and to non-gastrointestinal emergencies.
  • Journal article
    Kulendran M, Borovoi L, Purkayastha S, Darzi A, Vlaev Iet al., 2017,

    Impulsivity predicts weight loss after obesity surgery

    , Surgery for Obesity and Related Diseases, Vol: 13, Pages: 1033-1040, ISSN: 1550-7289

    ObjectiveThere is evidence that executive function, and specifically inhibitory control, is related to obesity and eating behavior. The goal of this study was to determine whether personality traits and inhibitory control predict weight loss after bariatric procedures. Although the impressive weight reduction after bariatric surgery has been shown in short- and medium-term studies, the effect of personality traits on this reduction is uncertain. Specifically, the effect of impulsivity is still largely unknown.SettingPatients attending either a multidisciplinary information session or outpatient clinic at the Imperial Weight Management Centre were recruited with informed consent into the trial over a 4-month period from January to April 2013. Participants were invited to attend behavioral testing on an outpatient basis in a silent room invigilated by a single researcher.MethodsForty-five bariatric patients participated in the study (25 patients had a gastric bypass, with a mean BMI of 41.8 and age of 39.0 years; 20 had a sleeve gastrectomy, with a mean BMI of 47.2 and age of 49.0 years). All patients completed personality measures of impulsivity—Barratt’s Impulsivity Scale, as well as behavioral measures of impulsivity—the stop-signal reaction-time (SSRT) task measuring inhibitory control and the temporal discounting task measuring reward processing. Those measures were examined in relation to weight loss 6 months after surgery.ResultsThe surgical procedure and changes in the behavioral measure of inhibitory control (SSRT) were found to be significant predictors of reduction in body mass index (BMI) in patients undergoing bariatric surgery. The sleeve gastrectomy group found a reduction in BMI of 14.1%, which was significantly less than the 25% reduction in BMI in the gastric bypass group. The direction (parameter estimate) of the significant effect was positive for SSRT change, which indicates that pre- and postreduction in impulsivity predicts red
  • Journal article
    Flott K, Hounsome L, Vuik S, Darzi A, Mayer Eet al., 2017,

    A patient-centric approach to improving experience in urological cancer care

    , Journal of Clinical Urology, Vol: 10, Pages: 39-46, ISSN: 2051-4166

    Rationale:Patient experience data are often reported at the provider level rather than the patient level, meaning that providers receive an aggregate score of all patient experience scores across their service. This inflates positivity and makes it difficult for providers to use patient experience scores to tailor improvements for patients within specific sites, wards or pathways. Patients have different priorities for their urological cancer care experience, and improvement programmes should take these differences into account. A more granular understanding of different patterns of patient experience will allow health care providers to focus their improvement strategies differently based on the needs of the patient groups that utilise their services.Objective:This study examines what groups exist within the urological cancer patient population, and what are their respective priorities for patient experience improvement.Methods:Using urological cancers as a case study, this paper uses data from the UK National Cancer Patient Experience Survey to segment the patient population based on their scores for 14 domains of experience. TwoStep cluster analyses were carried out on two groups of survey respondents: those who had an operation and those who did not. These analyses identified previously unknown clusters within the two populations. Profiles were created for each cluster based on a series of demographic variables, and a regression analysis was conducted to assess the significance of each demographic variable in determining cluster membership.Results:The TwoStep analysis yielded three clusters for both the operations and non-operations groups based on how patients experienced care: Positive, Middling and Negative. Gender, age, cancer type and income significantly influenced cluster membership: women, younger and more deprived patients were more prevalent in the Negative experience cluster.Conclusion:This more nuanced understanding of the patient population and the v
  • Conference paper
    Vuik SI, Mayer E, Darzi A, 2016,

    Understanding population health needs: How data-driven population segmentation can support the planning of integrated care

    , 16th International Conference on Integrated Care, Publisher: Utrecht University, Maastricht University, Groningen University, ISSN: 1568-4156
  • Journal article
    Rao AM, suliman A, vuik S, darzi, aylin Pet al., 2016,

    Systematic review of the use of hospital administrative data to assess functional decline

    , Journal of Aging Science, Vol: 4, ISSN: 2329-8847

    Introduction: Functional decline is commonly assessed by questionnaire-based surveys; however, administrative data can provide an alternative to evaluate functional decline. The aim of this study was to find out whether administrative data can be used to predict functional decline by conducting a systematic review of the literature.Methods: The methodology of the systematic review was based on PRISMA guidelines and PICOS process. The included studies were analyzed to identify different methods based on administrative to predict functional decline.Results: Three predictive models were developed from outcome measures based on administrative data. Firstly, model based on hospital readmissions was used to predict functional decline. Both model and survey results were compared to predict restricted activity days over 4 years’ duration. Hospital readmission based model had a predictive accuracy (AUC 0.69) like self-reported surveys (AUC 0.71 p 0.14). Secondly, procedural claims-based codes were used to construct a model that identified hospital procedures and services associated with functional decline. The model was compared to self-reported information on activities of daily living. It showed sensitivity of 0.79 and specificity of 0.92. Thirdly, post-operative imaging and reoperation codes were reviewed as predictive indicators, but were found to have no significant association with functional decline.Conclusion: Models based on hospital readmissions have the potential to be used widely because it has significant correlation with functional health and is a commonly recorded outcome measure in hospital administrative data. Its predictive accuracy is like self-reported functional health.
  • Journal article
    Vuik SI, Mayer E, Darzi A, 2016,

    Enhancing risk stratification for use in integrated care - A cluster analysis of high-risk patients in a retrospective cohort study

    , BMJ Open, Vol: 6, ISSN: 2044-6055

    Objective To show how segmentation can enhance risk stratification tools for integrated care, by providing insight into different care usage patterns within the high-risk population.Design A retrospective cohort study. A risk score was calculated for each person using a logistic regression, which was then used to select the top 5% high-risk individuals. This population was segmented based on the usage of different care settings using a k-means cluster analysis. Data from 2008 to 2011 were used to create the risk score and segments, while 2012 data were used to understand the predictive abilities of the models.Setting and participants Data were collected from administrative data sets covering primary and secondary care for a random sample of 300 000 English patients.Main measures The high-risk population was segmented based on their usage of 4 different care settings: emergency acute care, elective acute care, outpatient care and GP care.Results While the risk strata predicted care usage at a high level, within the high-risk population, usage varied significantly. 4 different groups of high-risk patients could be identified. These 4 segments had distinct usage patterns across care settings, reflecting different levels and types of care needs. The 2008–2011 usage patterns of the 4 segments were consistent with the 2012 patterns.Discussion Cluster analyses revealed that the high-risk population is not homogeneous, as there exist 4 groups of patients with different needs across the care continuum. Since the patterns were predictive of future care use, they can be used to develop integrated care programmes tailored to these different groups.Conclusions Usage-based segmentation augments risk stratification by identifying patient groups with different care needs, around which integrated care programmes can be designed.
  • Report
    Harris MJ, Bhatti Y, Prime M, del Castillo J, Parston G, Darzi Aet al., 2016,

    Global Diffusion of Healthcare Innovation: Making the Connections

    , Global Diffusion of Healthcare Innovation: Making the Connections, Publisher: Qatar Foundation
  • Conference paper
    Harris MJ, Bhatti Y, Prime M, del Castillo J, Parston G, Darzi Aet al., 2016,

    Global Diffusion of Healthcare Innovation: Making the Connections. Report for the World Innovation Summit for Health

    , World Innovation Summit for Health 2016, Publisher: World Innovation Summit for Health

    04GDHIEXECUTIVE SUMMARYThis research is part of the ongoing study of GDHI. The diffusion or spread of innova-tions over time through a specific population or social system is important to unlock the potential benefits of an innovation. There has been much study of how to encour-age the uptake of innovations so that they become part of everyday practice and ben-efit many, rather than a few. In this research, we explore this from the demand side. We explore how FHWs and leaders find solutions to their everyday challenges, and which sources are the most influential. We consider how these groups are sourcing solutions to their problems in six countries and how healthcare organizations can source innovations more effectively to meet the needs of FHWs and leaders. The study also explores the role that ‘curator organizations’ – a specialized set of organ-izations that source innovations from around the world – are playing in helping to diffuse innovations into clinical practice. We consider what role these organizations could play in future to ensure that they are relevant to frontline needs. The study builds on previous findings from 2013 GDHI research that showed how cer-tain system characteristics, enablers and frontline behaviors are critical to diffusion.1It follows on from the 2015 GDHI study that assessed the importance and prevalence of these elements in eight case studies of rapid, successfully scaled innovations.2This year, our study focuses on how FHWs and organization leaders source innova-tion in the first place. Our research draws on quantitative surveys of more than 1,350 FHWs in major urban centers of six countries (England, the United States (US), Qatar, Brazil, India and Tanzania). We conducted more than 90 personal interviews with healthcare leaders in these locations and in-depth conversations with the managers of 10 curator organizations.
  • Book chapter
    Pettengell CJ, Williams S, darzi A, 2016,

    Global Surgery: Progress and challenges in Surgical Quality and Patient Safety

    , Surgical Patient Care: Improving Safety, Quality and Value, Editors: sanchez, barach, Johnson, Jacobs, Publisher: Springer, ISBN: 978-3319440088
  • Journal article
    Vuik SI, Mayer E, Darzi A, 2016,

    A quantitative evidence base for population health: applying utilization-based cluster analysis to segment a patient population

    , Population Health Metrics, Vol: 14, ISSN: 1478-7954

    Background: To improve population health it is crucial to understand the different care needs within a population. Traditional population groups are often based on characteristics such as age or morbidities. However, this does not take into account specific care needs across care settings, and tends to focus on high needs patients only. This paper explores the potential of using utilisation-based cluster analysis to segment a general patient population into homogenous groups.Methods: Administrative datasets covering primary and secondary care were used to construct a database of 300,000 patients, which included socio-demographics variables, morbidities, care utilisation, and cost. A k-means cluster analysis grouped the patients into segments with distinct care utilisation, based on six utilisation variables: non-elective inpatient admissions, elective inpatient admissions, outpatient visits, GP practice visits, GP home visits, and prescriptions. These segments were analysed post-hoc to understand their morbidity and demographic profile.Results: Eight population segments were identified, and utilisation of each care setting was significantly different across all segments. Each segment also presented with different morbidity patterns and demographic characteristics, creating eight distinct care user types. Comparing these segments to traditional patient groups shows the heterogeneity of these approaches, especially for lower needs patients.Conclusions: This analysis shows that utilisation-based cluster analysis segments a patient population into distinct groups with unique care priorities, providing a quantitative evidence base to improve population health. Contrary to traditional methods, this approach also segments lower needs populations, which can be used to inform preventative interventions. In addition, the identification of different care user types provides insight into needs across the care continuum.
  • Journal article
    Flott K, Darzi A, Mayer E, 2016,

    Evaluation framework for patient safety incident reporting systems

    , International Journal for Quality in Health Care, Vol: 28, Pages: 8-9, ISSN: 1464-3677
  • Journal article
    Bagnall NM, Pucher PH, Johnston MJ, Arora S, Athanasiou T, Faiz O, Darzi LAet al., 2016,

    Informing the process of consent for surgery: identification of key constructs and quality factors

    , Journal of Surgical Research, Vol: 209, Pages: 86-92, ISSN: 0022-4804

    BackgroundInformed consent is a fundamental requirement of any invasive procedure. Failure to obtain appropriate and informed consent may result in unwanted or unnecessary procedures, as well as financial penalty in case of litigation. The aim of this study was to identify key constructs of the consent process which might be used to determine the performance of clinicians taking informed consent in surgery.MethodsA multimodal methodology was used. A systematic review was conducted in accordance with PRISMA guidelines to identify evidence-based components of the consent process. Results were supplemented by semistructured interviews with senior trainees and attending surgeons which were transcribed and subjected to emergent theme analysis with repeated sampling until thematic saturation was reached.ResultsA total of 710 search results were returned, with 26 articles included in the final qualitative synthesis of the systematic review. Significant variation existed between articles in the description of the consent procedure. Sixteen semistructured interviews were conducted before saturation was reached. Key components of the consent process were identified with broad consensus for the most common elements. Trainers felt that experiential learning and targeted skills training courses should be used to improve practice in this area.ConclusionsKey components for obtaining informed consent in surgery have been identified. These should be used to influence curricular design, possible assessment methods, and focus points to improve clinical practice and patient experience in future.
  • Journal article
    Hassen YAM, Singh P, Pucher PH, Johnston MJ, Darzi AWet al., 2016,

    Identifying Quality Markers of a Safe Surgical Ward: An Interview Study of Patients, Clinical Staff and Administrators

    , Journal of The American College of Surgeons, Vol: 223, Pages: S109-S110, ISSN: 1072-7515
  • Conference paper
    Modi HN, Leff D, Singh H, Darzi Aet al., 2016,

    Time in training does not predict performance deterioration under pressure

    , Association for Medical Education in Europe, Publisher: AMEE
  • Journal article
    Athanasiou T, Patel V, Garas G, Ashrafian H, Hull L, Sevdalis N, Harding S, Darzi A, Paroutis Set al., 2016,

    Mentoring perception, scientific collaboration and research performance: is there a ‘gender gap’ in academic medicine? An Academic Health Science Centre perspective

    , Postgraduate Medical Journal, ISSN: 1469-0756

    OBJECTIVES: The 'gender gap' in academic medicine remains significant and predominantly favours males. This study investigates gender disparities in research performance in an Academic Health Science Centre, while considering factors such as mentoring and scientific collaboration. MATERIALS AND METHODS: Professorial registry-based electronic survey (n=215) using bibliometric data, a mentoring perception survey and social network analysis. Survey outcomes were aggregated with measures of research performance (publications, citations and h-index) and measures of scientific collaboration (authorship position, centrality and social capital). Univariate and multivariate regression models were constructed to evaluate inter-relationships and identify gender differences. RESULTS: One hundred and four professors responded (48% response rate). Males had a significantly higher number of previous publications than females (mean 131.07 (111.13) vs 79.60 (66.52), p=0.049). The distribution of mentoring survey scores between males and females was similar for the quality and frequency of shared core, mentor-specific and mentee-specific skills. In multivariate analysis including gender as a variable, the quality of managing the relationship, frequency of providing corrective feedback and frequency of building trust had a statistically significant positive influence on number of publications (all p<0.05). CONCLUSIONS: This is the first study in healthcare research to investigate the relationship between mentoring perception, scientific collaboration and research performance in the context of gender. It presents a series of initiatives that proved effective in marginalising the gender gap. These include the Athena Scientific Women's Academic Network charter, new recruitment and advertisement strategies, setting up a 'Research and Family Life' forum, establishing mentoring circles for women and projecting female role models.
  • Conference paper
    Modi HN, Leff DR, Singh H, Darzi Aet al., 2016,

    Temporal Demands Increase Workload and Degrade Surgical Performance

    , International Surgical Congress of the Association of Surgeons of Great Britain and Ireland, Publisher: Wiley, Pages: 52-53, ISSN: 1365-2168
  • Journal article
    Vamos EP, Pape UJ, Curcin V, Harris MJ, Valabhji J, Majeed A, Millett C, Vamos EP, Pape UJ, Curcin V, Harris MJ, Valabhji J, Majeed A, Millett Cet al., 2016,

    Effectiveness of the influenza vaccine in preventing admission to hospital and death in people with type 2 diabetes.

    , Canadian Medical Association Journal, ISSN: 0008-4409

    BACKGROUND: The health burden caused by seasonal influenza is substantial. We sought to examine the effectiveness of influenza vaccination against admission to hospital for acute cardiovascular and respiratory conditions and all-cause death in people with type 2 diabetes. METHODS: We conducted a retrospective cohort study using primary and secondary care data from the Clinical Practice Research Datalink in England, over a 7-year period between 2003/04 and 2009/10. We enrolled 124 503 adults with type 2 diabetes. Outcome measures included admission to hospital for acute myocardial infarction (MI), stroke, heart failure or pneumonia/influenza, and death. We fitted Poisson regression models for influenza and off-season periods to estimate incidence rate ratios (IRR) for cohorts who had and had not received the vaccine. We used estimates for the summer, when influenza activity is low, to adjust for residual confounding. RESULTS: Study participants contributed to 623 591 person-years of observation during the 7-year study period. Vaccine recipients were older and had more comorbid conditions compared with nonrecipients. After we adjusted for covariates and residual confounding, vaccination was associated with significantly lower admission rates for stroke (IRR 0.70, 95% confidence interval [CI] 0.53-0.91), heart failure (IRR 0.78, 95% CI 0.65-0.92) and pneumonia or influenza (IRR 0.85, 95% CI 0.74-0.99), as well as all-cause death (IRR 0.76, 95% CI 0.65-0.83), and a nonsignificant change for acute MI (IRR 0.81, 95% CI 0.62-1.04) during the influenza seasons. INTERPRETATION: In this cohort of patients with type 2 diabetes, influenza vaccination was associated with reductions in rates of admission to hospital for specific cardiovascular events. Efforts should be focused on improvements in vaccine uptake in this important target group as part of comprehensive secondary prevention.

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-t4-html.jsp Request URI: /respub/WEB-INF/jsp/search-t4-html.jsp Query String: id=343&limit=20&page=2&respub-action=search.html Current Millis: 1610825083181 Current Time: Sat Jan 16 19:24:43 GMT 2021