508 research outputs found
Preferences for cancer investigation:a vignette-based study of primary-care attendees
SummaryBackgroundThe UK lags behind many European countries in terms of cancer survival. Initiatives to address this disparity have focused on barriers to presentation, symptom recognition, and referral for specialist investigation. Selection of patients for further investigation has come under particular scrutiny, although preferences for referral thresholds in the UK population have not been studied. We investigated preferences for diagnostic testing for colorectal, lung, and pancreatic cancers in primary-care attendees.MethodsIn a vignette-based study, researchers recruited individuals aged at least 40 years attending 26 general practices in three areas of England between Dec 6, 2011, and Aug 1, 2012. Participants completed up to three of 12 vignettes (four for each of lung, pancreatic, and colorectal cancers), which were randomly assigned. The vignettes outlined a set of symptoms, the risk that these symptoms might indicate cancer (1%, 2%, 5%, or 10%), the relevant testing process, probable treatment, possible alternative diagnoses, and prognosis if cancer were identified. Participants were asked whether they would opt for diagnostic testing on the basis of the information in the vignette.Findings3469 participants completed 6930 vignettes. 3052 individuals (88%) opted for investigation in their first vignette. We recorded no strong evidence that participants were more likely to opt for investigation with a 1% increase in risk of cancer (odds ratio [OR] 1·02, 95% CI 0·99–1·06; p=0·189), although the association between risk and opting for investigation was strong when colorectal cancer was analysed alone (1·08, 1·03–1·13; p=0·0001). In multivariable analysis, age had an effect in all three cancer models: participants aged 60–69 years were significantly more likely to opt for investigation than were those aged 40–59 years, and those aged 70 years or older were less likely. Other variables associated with increased likelihood of opting for investigation were shorter travel times to testing centre (colorectal and lung cancers), a family history of cancer (colorectal and lung cancers), and higher household income (colorectal and pancreatic cancers).InterpretationParticipants in our sample expressed a clear preference for diagnostic testing at all risk levels, and individuals want to be tested at risk levels well below those stipulated by UK guidelines. This willingness should be considered during design of cancer pathways, particularly in primary care. The public engagement with our study should encourage general practitioners to involve patients in referral decision making.FundingThe National Institute for Health Research Programme Grants for Applied Research programme
Effects of Bulk and Surface Conductivity on the Performance of CdZnTe Pixel Detectors
We studied the effects of bulk and surface conductivity on the performance of
high-resistivity CdZnTe (CZT) pixel detectors with Pt contacts. We emphasize
the difference in mechanisms of the bulk and surface conductivity as indicated
by their different temperature behaviors. In addition, the existence of a thin
(10-100 A) oxide layer on the surface of CZT, formed during the fabrication
process, affects both bulk and surface leakage currents. We demonstrate that
the measured I-V dependencies of bulk current can be explained by considering
the CZT detector as a metal-semiconductor-metal system with two back-to-back
Schottky-barrier contacts. The high surface leakage current is apparently due
to the presence of a low-resistivity surface layer that has characteristics
which differ considerably from those of the bulk material. This surface layer
has a profound effect on the charge collection efficiency in detectors with
multi-contact geometry; some fraction of the electric field lines originated on
the cathode intersects the surface areas between the pixel contacts where the
charge produced by an ionizing particle gets trapped. To overcome this effect
we place a grid of thin electrodes between the pixel contacts; when the grid is
negatively biased, the strong electric field in the gaps between the pixels
forces the electrons landing on the surface to move toward the contacts,
preventing the charge loss. We have investigated these effects by using CZT
pixel detectors indium bump bonded to a custom-built VLSI readout chip
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Identifying novel biomarkers ready for evaluation in low-prevalence populations for the early detection of upper gastrointestinal cancers: a systematic review
Introduction: Detecting upper gastrointestinal (GI) cancers in primary care is challenging as cancer symptoms are common, often non-specific, and most patients presenting with these symptoms will not have cancer. Substantial investment has been made to develop biomarkers for cancer detection, but few have reached routine clinical practice. We aimed to identify novel biomarkers for upper GI cancers which have been validated sufficiently to be ready for evaluation in low-prevalence populations.
Methods: We systematically searched MEDLINE, Embase, Emcare, and Web of Science for studies published in English from January 2000 to October 2019 (PROSPERO registration CRD42020165005). Reference lists of included studies were assessed. Studies had to report on second measures of diagnostic performance (beyond discovery phase) for biomarkers (single or in panels) used to detect pancreatic, oesophageal, gastric, and biliary tract cancers. We included all designs and excluded studies with less than 50 cases/controls. Data were extracted on types of biomarkers, populations and outcomes. Heterogeneity prevented pooling of outcomes.
Results: We identified 149 eligible studies, involving 22,264 cancer cases and 49,474 controls. 431 biomarkers were identified (183 microRNAs and other RNAs, 79 autoantibodies and other immunological markers, 119 other proteins, 36 metabolic markers, 6 circulating tumour DNA and 8 other). Over half (n=231) were reported in pancreatic cancer studies. Only 35 biomarkers had been investigated in at least two studies, with reported outcomes for that individual marker for the same tumour type. Apolipoproteins apoAII-AT and apoAII-ATQ and pepsinogens PGI and PGII were the most promising biomarkers for pancreatic and gastric cancer respectively.
Conclusion: Most novel biomarkers for the early detection of upper GI cancers are still at an early stage of matureness. Further evidence is needed on biomarker performance in low-prevalence populations, in addition to implementation and health economic studies, before extensive adoption into clinical practice can be recommended.Cancer Research UK C8640/A23385)
Paige Druce, Kristi Milley and Jon Emery are supported by the Cancer Australia Primary Care Collaborative Cancer Clinical Trials Group (PC4). Mike Messenger is funded by the NIHR Leeds In Vitro Diagnostic Co-operative (UK
Total skin self-examination at home for people treated for cutaneous melanoma : development and pilot of a digital intervention
This work was funded by the RCUK Digital Economy award to the dot.rural Digital Economy Hub, University of Aberdeen; award reference: EP/G066051/1. The Experience Laboratory event was supported in part by a separate award from the University of Aberdeen Knowledge Exchange and Transfer Fund; award reference: GP057 UZZ0101.Peer reviewedPublisher PD
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Effectiveness of interventions for improving timely diagnosis of breast and cervical cancers in low and middle-income countries: a systematic review protocol.
INTRODUCTION: Breast and cervical cancers pose a major public health burden globally, with disproportionately high incidence, morbidity and mortality in low- and middle-income countries (LMICs). The majority of women diagnosed with cancer in LMICs present with late-stage disease, the treatment of which is often costlier and less effective. While interventions to improve the timely diagnosis of these cancers are increasingly being implemented in LMICs, there is uncertainty about their role and effectiveness. The aim of this review is to systematically synthesise available evidence on the nature and effectiveness of interventions for improving timely diagnosis of breast and cervical cancers in LMICs. METHODS AND ANALYSIS: A comprehensive search of published and relevant grey literature will be conducted. The following electronic databases will be searched: MEDLINE (via PubMed), Cochrane Library, Scopus, CINAHL, Web of Science and the International Clinical Trials Registry Platform (ICTRP). Evidence will be synthesised in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). Two reviewers will independently screen the search outputs, select studies using predefined inclusion criteria and assess each included study for risk of bias. If sufficient data are available and studies are comparable in terms of interventions and outcomes, a meta-analysis will be conducted. Where studies are not comparable and a meta-analysis is not appropriate, a narrative synthesis of findings will be reported. ETHICS AND DISSEMINATION: As this will be a systematic review of publicly available data, with no primary data collection, it will not require ethical approval. Findings will be disseminated widely through a peer-reviewed publication and forums such as conferences, workshops and community engagement sessions. This review will provide a user-friendly evidence summary for informing further efforts at developing and implementing interventions for addressing delays in breast and cervical cancer diagnosis in LMICs. PROSPERO REGISTRATION NUMBER: CRD42020177232.This research was jointly supported by the Cancer Association of South Africa (CANSA), the University of Cape Town and the SA Medical Research Council with funds received from the SA National Department of Health, GlaxoSmithKline Africa Non-Communicable Disease Open Lab (via a supporting grant, Project Number: 023), the UK Medical Research Council (via the Newton Fund). FMW is Director of the multi-institutional CanTest Collaborative, which is funded by Cancer Research UK (C8640/A23385). Authors retained control of the final content of the publication
Timeliness of diagnosis of breast and cervical cancers and associated factors in low-income and middle-income countries: a scoping review protocol.
INTRODUCTION: Breast and cervical cancer are leading causes of morbidity and mortality in women globally, with disproportionately high burdens in low-income and middle-income countries (LMICs). While the incidence of both cancers increases across LMICs, many cases continue to go undiagnosed or diagnosed late. The aim of this review is to comprehensively map the current evidence on the time to breast or cervical cancer diagnosis and its associated factors in LMICs. METHODS AND ANALYSIS: This scoping review (ScR) will be informed by Arksey and O'Malley's enhanced ScR methodology framework. It will be reported in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews. We will conduct a comprehensive search of the following electronic databases: MEDLINE (via PubMed), Cochrane Library, Scopus and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). Two reviewers will independently screen all abstracts and full texts using predefined inclusion criteria. All publications describing the time to diagnosis and its associated factors in the contexts of breast or cervical cancer will be considered for inclusion. Evidence will be narratively synthesised and analysed using a predefined conceptual framework. ETHICS AND DISSEMINATION: As this is a ScR of publicly available data, with no primary data collection, it will not require ethical approval. Findings will be disseminated widely through a peer-reviewed publication and forums such as conferences and community engagement sessions. This review will provide a user-friendly evidence summary for understanding the enormity of diagnostic delays and associated factors for breast and cervical cancers in LMICs, while helping to inform policy actions and implementation of interventions for addressing such delays
What are the key elements of educational interventions for lay carers of patients with advanced disease? A systematic literature search and narrative review of structural components, processes and modes of delivery
Context: Educating carers about symptom management may help meet patient and carer needs in relation to distressing symptoms in advanced disease. Reviews of the effectiveness of carer interventions exist, but few have focused on educational interventions and none on the key elements that comprise them but which could inform evidence-based design. Objectives: To identify the key elements (structural components, processes, and delivery modes) of educational interventions for carers of patients with advanced disease. Methods: We systematically searched seven databases, applied inclusion and exclusion criteria, conducted quality appraisal, extracted data, and performed a narrative analysis. Results: We included 62 articles related to 49 interventions. Two main delivery modes were identified: personnel-delivered interventions and stand-alone resources. Personnel-delivered interventions targeted individuals or groups, the former conducted at single or multiple time points, and the latter delivered as series. Just more than half targeted carers rather than patient-carer dyads. Most were developed for cancer; few focused purely on symptom management. Stand-alone resources were rare. Methods to evaluate interventions ranged from postintervention evaluations to fully powered randomized controlled trials but of variable quality. Conclusion: Published evaluations of educational interventions for carers in advanced disease are limited, particularly for non-cancer conditions. Key elements for consideration in developing such interventions were identified; however, lack of reporting of reasons for nonparticipation or dropout from interventions limits understanding of the contribution of these elements to interventions' effectiveness. When developing personnel-delivered interventions for carers in advanced disease, consideration of the disease (and, therefore, caring) trajectory, intervention accessibility (timing, location, and transport), and respite provision may be helpful
Patient understanding of moles and skin cancer, and factors influencing presentation in primary care: a qualitative study.
BACKGROUND: Melanoma incidence in the UK has doubled over two decades, yet there is conflicting evidence about factors which prompt or delay patients seeking advice. AIM: To explore patient understanding of pigmented skin lesions (moles) and skin cancer, and factors which influence seeking help in primary care. METHOD: Semi-structured interviews with forty MoleMate Trial participants, analysed using the theoretical framework of the Safer-Andersen model of Total Patient Delay. RESULTS: Patient understanding and awareness was influenced by personal, family and friends' experiences of moles, skin cancer and other cancers, knowledge of risk factors, and the lay media. The route to consulting was complex and often iterative. For lesions that people could see, detecting and appraising change was influenced by comparisons with a normal mole on themselves, a family member, friend or image. Inferring illness came about with recognition of changes (particularly size) as serious, and associated 'internal' symptoms such as pain. For lesions that people could not see, family, friends and health professionals detected and appraised changes. Deciding to seek help was often prompted by another person or triggered by rapid or multiple changes in a mole. Three of four people subsequently diagnosed with melanoma did not seek help; instead, their GP opportunistically noticed the lesion. CONCLUSIONS: Changing moles are often perceived as trivial and not signifying possible skin cancer. This study contributes to current national strategies to improve patient awareness and earlier diagnosis of cancer by highlighting factors that can trigger or act as barriers to seeking help.(ISRCTN79932379).RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Understanding implementation and usefulness of electronic clinical decision support (eCDS) for melanoma in English primary care: a qualitative investigation.
BACKGROUND: Timely diagnosis of the serious skin cancer melanoma can improve patient outcomes. Clinical guidelines suggest that GPs use checklists, such as the 7-point checklist (7PCL), to assess pigmented lesions. In 2016, the 7PCL was disseminated by EMIS as an electronic clinical decision support (eCDS) tool. AIM: To understand GP and patient perspectives on the implementation and usefulness of the eCDS. DESIGN & SETTING: Semi-structured interviews with GPs and patients were undertaken. The interviews took place in four general practices in the south east of England following consultations using the eCDS for suspicious pigmented lesions. METHOD: Data were collected from semi-structured face-to-face interviews with GPs and from telephone interviews with patients. They were recorded and transcribed verbatim. The Consolidated Framework for Implementation Research (CFIR) underpinned the analysis using thematic approaches. RESULTS: A total of 14 interviews with GPs and 14 interviews with patients were undertaken. Most GPs reported that, as the eCDS was embedded in the medical record, it was useful, easy to use, time-efficient, and could facilitate patient-GP communication. They were less clear that it could meet policy or patient needs to improve early diagnosis, and some felt that it could lead to unnecessary referrals. Few felt that it had been sufficiently implemented at practice level. More felt confident with their own management of moles, and that the eCDS could be most useful for borderline decision-making. No patients were aware that the eCDS had been used during their consultation. CONCLUSION: Successful implementation of a new tool, such as eCDS for melanoma, requires GPs to perceive its value and understand how it can best be integrated into clinical practice. Disseminating a tool without such explanations is unlikely to promote its adoption into routine practice.NIH
Risk prediction models for melanoma: a systematic review.
Melanoma incidence is increasing rapidly worldwide among white-skinned populations. Earlier diagnosis is the principal factor that can improve prognosis. Defining high-risk populations using risk prediction models may help targeted screening and early detection approaches. In this systematic review, we searched Medline, EMBASE, and the Cochrane Library for primary research studies reporting or validating models to predict risk of developing cutaneous melanoma. A total of 4,141 articles were identified from the literature search and six through citation searching. Twenty-five risk models were included. Between them, the models considered 144 possible risk factors, including 18 measures of number of nevi and 26 of sun/UV exposure. Those most frequently included in final risk models were number of nevi, presence of freckles, history of sunburn, hair color, and skin color. Despite the different factors included and different cutoff values for sensitivity and specificity, almost all models yielded sensitivities and specificities that fit along a summary ROC with area under the ROC (AUROC) of 0.755, suggesting that most models had similar discrimination. Only two models have been validated in separate populations and both also showed good discrimination with AUROC values of 0.79 (0.70-0.86) and 0.70 (0.64-0.77). Further research should focus on validating existing models rather than developing new ones.This report is independent research arising from a Clinician Scientist
award supported by the National Institute for Health Research (RG 68235) and J Usher-Smith
is funded by a National Institute for Health Research Clinical LectureshipThis is the author accepted manuscript. The advanced access published version can be found on the publisher's website at: http://cebp.aacrjournals.org/content/early/2014/06/03/1055-9965.EPI-14-0295.abstrac
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