923 resultados para RESEARCH DIAGNOSTIC-CRITERIA
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BACKGROUND AND AIMS: Internet-based surveys provide a potentially important tool for Inflammatory Bowel Disease (IBD) research. The advantages include low cost, large numbers of participants, rapid study completion and less extensive infrastructure than traditional methods. The aim was to determine the accuracy of patient self-reporting in internet-based IBD research and identify predictors of greater reliability. METHODS: 197 patients from a tertiary care center answered an online survey concerning personal medical history and an evaluation of disease specific knowledge. Self-reported medical details were compared with data abstracted from medical records. Agreement was assessed by kappa (κ) statistics. RESULTS: Participants responded correctly with excellent agreement (κ=0.96-0.97) on subtype of IBD and history of surgery. The agreement was also excellent for colectomy (κ=0.88) and small bowel resection (κ=0.91), moderate for abscesses and fistulas (κ=0.60 and 0.63), but poor regarding partial colectomy (κ=0.39). Time since last colonoscopy was self-reported with better agreement (κ=0.84) than disease activity. For disease location/extent, moderate agreements at κ=69% and 64% were observed for patients with Crohn's disease and ulcerative colitis, respectively. Subjects who scored higher than the average in the IBD knowledge assessment were significantly more accurate about disease location than their complementary group (74% vs. 59%, p=0.02). CONCLUSION: This study demonstrates that IBD patients accurately report their medical history regarding type of disease and surgical procedures. More detailed medical information is less reliably reported. Disease knowledge assessment may help in identifying the most accurate individuals and could therefore serve as validity criteria. Internet-based surveys are feasible with high reliability about basic disease features only. However, the participants in this study were engaged at a tertiary center, which potentially leads to a bias and compromises generalization to an unfiltered patient group.
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Cerebrovascular diseases are significant causes of death and disability in humans. Improvements in diagnostic and therapeutic approaches strongly rely on adequate gyrencephalic, large animal models being demanded for translational research. Ovine stroke models may represent a promising approach but are currently limited by insufficient knowledge regarding the venous system of the cerebral angioarchitecture. The present study was intended to provide a comprehensive anatomical analysis of the intracranial venous system in sheep as a reliable basis for the interpretation of experimental results in such ovine models. We used corrosion casts as well as contrast-enhanced magnetic resonance venography to scrutinize blood drainage from the brain. This combined approach yielded detailed and, to some extent, novel findings. In particular, we provide evidence for chordae Willisii and lateral venous lacunae, and report on connections between the dorsal and ventral sinuses in this species. For the first time, we also describe venous confluences in the deep cerebral venous system and an 'anterior condylar confluent' as seen in humans. This report provides a detailed reference for the interpretation of venous diagnostic imaging findings in sheep, including an assessment of structure detectability by in vivo (imaging) versus ex vivo (corrosion cast) visualization methods. Moreover, it features a comprehensive interspecies-comparison of the venous cerebral angioarchitecture in man, rodents, canines and sheep as a relevant large animal model species, and describes possible implications for translational cerebrovascular research.
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This contribution focuses on the characteristics of the school context and their impact on immigrant students’ acculturation and adjustment at school. Research suggests that the ways immigrants acculturate is related to their well being (e.g. Phinney, et al., 2001; Ward & Rana-Deuba, 1999), although findings have been contradictory across methods and studies (e.g. Rogler, 1991; Escobar & Vega, 2001). Debates in acculturation research currently center on issues of acculturation measurement (e.g. Berry, 2009; Rudmin, 2009), as most research is conducted in the quantitative tradition. In addition, some have suggested (Birman, 2011) that research on acculturation in the tradition of cross-cultural psychology adopts an overly individualistic perspective, and lacks attention to the specific contexts of acculturation. Alternatively, the contextual approach proposes that the relationship between acculturation and adjustment is shaped by the surrounding context (Birman & Simon, 2013). For immigrant children, schools are the setting where the process of acculturation unfolds, and an important context in which to study their adjustment and well being (Birman, et al., 2007; Makarova & Herzog, 2011). Though rarely used in this tradition of acculturation research (Chirkov, 2009), qualitative methods are uniquely suited to gain insight to facilitate theory development, as well as appreciate the contextual nature of the acculturation process. Yet we are not aware of efforts to synthesize the empirical qualitative literature on this topic. Applying the methodology of meta-synthesis for qualitatieve research (Walsh & Downe, 2005) our contribution attempts to integrate results from qualitative studies on impact of acculturation on immigrant students’ psychological adjustment in the school context. For this purpose 84 articles which matched the inclusion criteria were selected. Overall, the results of our study show that within the school context a number of structural as well as process characteristics can be identified as crucial for immigrant youth psychological adjustment. Moreover, our findings indicate that immigrant youths’ psychological adjustment is related to other individual outcomes of acculturation in the school context such as behavioral adjustment, peer-relationships, academic achievement and identity development of immigrant youth.
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BACKGROUND AND PURPOSE Intensity-modulated radiotherapy (IMRT) credentialing for a EORTC study was performed using an anthropomorphic head phantom from the Radiological Physics Center (RPC; RPC(PH)). Institutions were retrospectively requested to irradiate their institutional phantom (INST(PH)) using the same treatment plan in the framework of a Virtual Phantom Project (VPP) for IMRT credentialing. MATERIALS AND METHODS CT data set of the institutional phantom and measured 2D dose matrices were requested from centers and sent to a dedicated secure EORTC uploader. Data from the RPC(PH) and INST(PH) were thereafter centrally analyzed and inter-compared by the QA team using commercially available software (RIT; ver.5.2; Colorado Springs, USA). RESULTS Eighteen institutions participated to the VPP. The measurements of 6 (33%) institutions could not be analyzed centrally. All other centers passed both the VPP and the RPC ±7%/4 mm credentialing criteria. At the 5%/5 mm gamma criteria (90% of pixels passing), 11(92%) as compared to 12 (100%) centers pass the credentialing process with RPC(PH) and INST(PH) (p = 0.29), respectively. The corresponding pass rate for the 3%/3 mm gamma criteria (90% of pixels passing) was 2 (17%) and 9 (75%; p = 0.01), respectively. CONCLUSIONS IMRT dosimetry gamma evaluations in a single plane for a H&N prospective trial using the INST(PH) measurements showed agreement at the gamma index criteria of ±5%/5 mm (90% of pixels passing) for a small number of VPP measurements. Using more stringent, criteria, the RPC(PH) and INST(PH) comparison showed disagreement. More data is warranted and urgently required within the framework of prospective studies.
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Starting from the early descriptions of Kraepelin and Bleuler, the construct of schizotypy was developed from observations of aberrations in nonpsychotic family members of schizophrenia patients. In contemporary diagnostic manuals, the positive symptoms of schizotypal personality disorder were included in the ultra high-risk (UHR) criteria 20 years ago, and nowadays are broadly employed in clinical early detection of psychosis. The schizotypy construct, now dissociated from strict familial risk, also informed research on the liability to develop any psychotic disorder, and in particular schizophrenia-spectrum disorders, even outside clinical settings. Against the historical background of schizotypy it is surprising that evidence from longitudinal studies linking schizotypy, UHR, and conversion to psychosis has only recently emerged; and it still remains unclear how schizotypy may be positioned in high-risk research. Following a comprehensive literature search, we review 18 prospective studies on 15 samples examining the evidence for a link between trait schizotypy and conversion to psychosis in 4 different types of samples: general population, clinical risk samples according to UHR and/or basic symptom criteria, genetic (familial) risk, and clinical samples at-risk for a nonpsychotic schizophrenia-spectrum diagnosis. These prospective studies underline the value of schizotypy in high-risk research, but also point to the lack of evidence needed to better define the position of the construct of schizotypy within a developmental psychopathology perspective of emerging psychosis and schizophrenia-spectrum disorders
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Venous thromboembolism (VTE) is a potentially lethal clinical condition that is suspected in patients with common clinical complaints, in many and varied, clinical care settings. Once VTE is diagnosed, optimal therapeutic management (thrombolysis, IVC filters, type and duration of anticoagulants) and ideal therapeutic management settings (outpatient, critical care) are also controversial. Clinical prediction tools, including clinical decision rules and D-Dimer, have been developed, and some validated, to assist clinical decision making along the diagnostic and therapeutic management paths for VTE. Despite these developments, practice variation is high and there remain many controversies in the use of the clinical prediction tools. In this narrative review, we highlight challenges and controversies in VTE diagnostic and therapeutic management with a focus on clinical decision rules and D-Dimer.
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Histomorphological features of colorectal cancers (CRC) represent valuable prognostic indicators for clinical decision making. The invasive margin is a central feature for prognostication shaped by the complex processes governing tumor-host interaction. Assessment of the tumor border can be performed on standard paraffin sections and shows promise for integration into the diagnostic routine of gastrointestinal pathology. In aggressive CRC, an extensive dissection of host tissue is seen with loss of a clear tumor-host interface. This pattern, termed "infiltrative tumor border configuration" has been consistently associated with poor survival outcome and early disease recurrence of CRC-patients. In addition, infiltrative tumor growth is frequently associated with presence of adverse clinicopathological features and molecular alterations related to aggressive tumor behavior including BRAFV600 mutation. In contrast, a well-demarcated "pushing" tumor border is seen frequently in CRC-cases with low risk for nodal and distant metastasis. A pushing border is a feature frequently associated with mismatch-repair deficiency and can be used to identify patients for molecular testing. Consequently, assessment of the tumor border configuration as an additional prognostic factor is recommended by the AJCC/UICC to aid the TNM-classification. To promote the assessment of the tumor border configuration in standard practice, consensus criteria on the defining features and method of assessment need to be developed further and tested for inter-observer reproducibility. The development of a standardized quantitative scoring system may lay the basis for verification of the prognostic associations of the tumor growth pattern in multivariate analyses and clinical trials. This article provides a comprehensive review of the diagnostic features, clinicopathological associations, and molecular alterations associated with the tumor border configuration in early stage and advanced CRC.
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Objective To discuss the diagnostic validity of unusual bodily perceptions along the spectrum from age-specific, often transitory and normal, to pathological phenomena in adolescence to hypochondriasis and finally to psychosis. Methods Critical literature review of the cornerstone diagnostic groups along the spectrum embracing anxiety and cenesthopathy in adolescence, hypochondriasis, and cenesthopathy and psychosis, followed by a discussion of the diagnostic overlaps along this spectrum. Results The review highlights significant overlaps between the diagnostic cornerstones. It is apparent that adolescents with unusual bodily perceptions may conceptually qualify for more than one diagnostic group along the spectrum. To determine whether cenesthopathies in adolescence mirror emerging psychosis, a number of issues need to be considered, i.e. age and mode of onset, gender, level of functioning and drug use. The role of overvalued ideas at the border between hypochondriasis and psychosis must be considered. Conclusion As unusual bodily symptoms may in some instances meet formal psychosis risk criteria, a narrow understanding of these symptoms may lead to both inappropriate application of the new DSM-5 attenuated psychosis syndrome and of treatment selection. On the other hand, the possibility of a psychotic dimension of unusual bodily symptoms in adolescents must always be considered as most severe expression of the cenesthopathy spectrum.
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BACKGROUND Retinal optical coherence tomography (OCT) permits quantification of retinal layer atrophy relevant to assessment of neurodegeneration in multiple sclerosis (MS). Measurement artefacts may limit the use of OCT to MS research. OBJECTIVE An expert task force convened with the aim to provide guidance on the use of validated quality control (QC) criteria for the use of OCT in MS research and clinical trials. METHODS A prospective multi-centre (n = 13) study. Peripapillary ring scan QC rating of an OCT training set (n = 50) was followed by a test set (n = 50). Inter-rater agreement was calculated using kappa statistics. Results were discussed at a round table after the assessment had taken place. RESULTS The inter-rater QC agreement was substantial (kappa = 0.7). Disagreement was found highest for judging signal strength (kappa = 0.40). Future steps to resolve these issues were discussed. CONCLUSION Substantial agreement for QC assessment was achieved with aid of the OSCAR-IB criteria. The task force has developed a website for free online training and QC certification. The criteria may prove useful for future research and trials in MS using OCT as a secondary outcome measure in a multi-centre setting.
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OBJECTIVE To provide guidance on standards for reporting studies of diagnostic test accuracy for dementia disorders. METHODS An international consensus process on reporting standards in dementia and cognitive impairment (STARDdem) was established, focusing on studies presenting data from which sensitivity and specificity were reported or could be derived. A working group led the initiative through 4 rounds of consensus work, using a modified Delphi process and culminating in a face-to-face consensus meeting in October 2012. The aim of this process was to agree on how best to supplement the generic standards of the STARD statement to enhance their utility and encourage their use in dementia research. RESULTS More than 200 comments were received during the wider consultation rounds. The areas at most risk of inadequate reporting were identified and a set of dementia-specific recommendations to supplement the STARD guidance were developed, including better reporting of patient selection, the reference standard used, avoidance of circularity, and reporting of test-retest reliability. CONCLUSION STARDdem is an implementation of the STARD statement in which the original checklist is elaborated and supplemented with guidance pertinent to studies of cognitive disorders. Its adoption is expected to increase transparency, enable more effective evaluation of diagnostic tests in Alzheimer disease and dementia, contribute to greater adherence to methodologic standards, and advance the development of Alzheimer biomarkers.
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Lumbar spinal instability (LSI) is a common spinal disorder and can be associated with substantial disability. The concept of defining clinically relevant classifications of disease or 'target condition' is used in diagnostic research. Applying this concept to LSI we hypothesize that a set of clinical and radiological criteria can be developed to identify patients with this target condition who are at high risk of 'irreversible' decompensated LSI for whom surgery becomes the treatment of choice. In LSI, structural deterioration of the lumbar disc initiates a degenerative cascade of segmental instability. Over time, radiographic signs become visible: traction spurs, facet joint degeneration, misalignment, stenosis, olisthesis and de novo scoliosis. Ligaments, joint capsules, local and distant musculature are the functional elements of the lumbar motion segment. Influenced by non-functional factors, these functional elements allow a compensation of degeneration of the motion segment. Compensation may happen on each step of the degenerative cascade but cannot reverse it. However, compensation of LSI may lead to an alleviation or resolution of clinical symptoms. In return, the target condition of decompensation of LSI may cause the new occurrence of symptoms and pain. Functional compensation and decompensation are subject to numerous factors that can change which makes estimation of an individual's long-term prognosis difficult. Compensation and decompensation may influence radiographic signs of degeneration, e.g. the degree of misalignment and segmental angulation caused by LSI is influenced by the tonus of the local musculature. This conceptual model of compensation/decompensation may help solve the debate on functional and psychosocial factors that influence low back pain and to establish a new definition of non-specific low back pain. Individual differences of identical structural disorders could be explained by compensated or decompensated LSI leading to changes in clinical symptoms and pain. Future spine surgery will have to carefully define and measure functional aspects of LSI, e.g. to identify a point of no return where multidisciplinary interventions do not allow a re-compensation and surgery becomes the treatment of choice.
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OBJECTIVES Evaluation of computed tomography (CT) and magnetic resonance imaging (MRI) for differentiation of pancreatic intraductal papillary mucinous neoplasm (IPMN) subtypes based on objective imaging criteria. METHODS Fifty-eight patients with 60 histologically confirmed IPMNs were included in this retrospective study. Eighty-three imaging studies (CT,n = 42; MRI,n = 41) were analysed by three independent blinded observers (O1-O3), using established imaging criteria to assess likelihood of malignancy (-5, very likely benign; 5, very likely malignant) and histological subtype (i.e., low-grade (LGD), moderate-grade (MGD), high-grade dysplasia (HGD), early invasive carcinoma (IPMC), solid carcinoma (CA) arising from IPMN). RESULTS Forty-one benign (LGD IPMN,n = 20; MGD IPMN,n = 21) and 19 malignant (HGD IPMN,n = 3; IPMC,n = 6; solid CA,n = 10) IPMNs located in the main duct (n = 6), branch duct (n = 37), or both (n = 17) were evaluated. Overall accuracy of differentiation between benign and malignant IPMNs was 86/92 % (CT/MRI). Exclusion of overtly malignant cases (solid CA) resulted in overall accuracy of 83/90 % (CT/MRI). The presence of mural nodules and ductal lesion size ≥30 mm were significant indicators of malignancy (p = 0.02 and p < 0.001, respectively). CONCLUSIONS Invasive IPMN can be identified with high confidence and sensitivity using CT and MRI. The diagnostic problem that remains is the accurate radiological differentiation of premalignant and non-invasive subtypes. KEY POINTS • CT and MRI can differentiate benign from malignant forms of IPMN. • Identifying (pre)malignant histological IPMN subtypes by CT and MRI is difficult. • Overall, diagnostic performance with MRI was slightly (not significantly) superior to CT.
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Lung cancer remains the most common cause of cancer deaths worldwide, yet there is currently a lack of diagnostic noninvasive biomarkers that could guide treatment decisions. Small molecules (<1,500 Da) were measured in urine collected from 469 patients with lung cancer and 536 population controls using unbiased liquid chromatography/mass spectrometry. Clinical putative diagnostic and prognostic biomarkers were validated by quantitation and normalized to creatinine levels at two different time points and further confirmed in an independent sample set, which comprises 80 cases and 78 population controls, with similar demographic and clinical characteristics when compared with the training set. Creatine riboside (IUPAC name: 2-{2-[(2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)-oxolan-2-yl]-1-methylcarbamimidamido}acetic acid), a novel molecule identified in this study, and N-acetylneuraminic acid (NANA) were each significantly (P < 0.00001) elevated in non-small cell lung cancer and associated with worse prognosis [HR = 1.81 (P = 0.0002), and 1.54 (P = 0.025), respectively]. Creatine riboside was the strongest classifier of lung cancer status in all and stage I-II cases, important for early detection, and also associated with worse prognosis in stage I-II lung cancer (HR = 1.71, P = 0.048). All measurements were highly reproducible with intraclass correlation coefficients ranging from 0.82 to 0.99. Both metabolites were significantly (P < 0.03) enriched in tumor tissue compared with adjacent nontumor tissue (N = 48), thus revealing their direct association with tumor metabolism. Creatine riboside and NANA may be robust urinary clinical metabolomic markers that are elevated in tumor tissue and associated with early lung cancer diagnosis and worse prognosis.
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Introduction: In professional soccer, talent selection relies on the subjective judgment of scouts and coaches. To date, little is known about coaches´ “eye for talent” (Christensen, 2009, p. 379) and the nature of the subjective criteria they use to identify those players with the greatest potential to achieve peak performance in adulthood (Williams & Reilly, 2000). Drawing on a constructivist approach (Kelly, 1991), this study explores coaches´ subjective talent criteria. It is assumed that coaches are able to verbalise and specify their talent criteria, and that these are related to their talent selection decisions based on instinct. Methods: Participants and generation of data. Five national youth soccer coaches (Mage = 55.6; SD = 5.03) were investigated at three appointments: (1) talent selection decision based on instinct, (2) semi-structured inductive interview to elicit each coaches´ talent criteria in detail, (3) communicative validation and evaluation of the players by each coach using the repertory grid technique (Fromm, 2004). Data Analysis: Interviews were transcribed and summarized with regard to each specified talent criterion. Each talent criterion was categorized using a bottom-up-approach (meaning categorization, Kvale, 1996). The repertory grid data was analysed using descriptive statistics and correlation analysis. Results and Discussion: For each coach, six to nine talent criteria were elicited and specified. The subjective talent criteria include aspects of personality, cognitive perceptual skills, motor abilities, development, technique, social environment and physical constitution, which shows that the coaches use a multi-dimensional concept of talent. However, more than half of all criteria describe personality characteristics, in particular achievement motivation, volition and self-confidence. In contrast to Morris (2000), this result shows that coaches have a differentiated view of the personality characteristics required to achieve peak performance. As an indication of criterion validity, moderate to high correlations (.57 ≤ r ≤ .81) are found between the evaluations of the players according to the coaches´ talent criteria and their talent selection decision. The study shows that coaches are able to specify their subject talent criteria and that those criteria are strongly related to their instinctive selection decisions. References: Christensen, M. K. (2009). "An Eye for Talent": Talent Identification and the "Practical Sense" of Top-Level Soccer Coaches. Sociology of Sport Journal, 26, 365–382. Fromm, M. (2004). Introduction to the Repertory Grid Interview. Münster: Waxmann. Kelly, G. A. (1991). The Psychology of Personal Constructs: Volume One: Theory and personality. London: Routledge. Kvale, S. (1996). InterViews: An introduction to Qualitative Research Interviewing. Thousand Oaks: Sage. Morris, T. (2000). Psychological characteristics and talent identification in soccer. Journal of Sports Sciences, 18, 715–726. Williams, A. M., & Reilly, T. (2000). Talent identification and development in soccer. Journal of Sports Sciences, 18, 657–667.
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Critical situations (CSs) involving football fans is a well-researched phenomenon with most studies examining factors leading to an escalation of violence (e.g. Braun & Vliegenthart, 2008). However, research so far has fallen short of analysing CSs that do not escalate (e.g. Hylander & Guvå, 2010) as well as establishing observable criteria that constitute such CSs. Granström et al. (2009), for instance, put forward a definition of a CS describing such situations as characterised by a discrepancy between peace and war-making behaviours between police and demonstrators. Still, this definition remains vague and does not provide concrete, defining criteria that can be identified on site. The present study looks beyond fans’ violent acts per se and focuses on these situations with a potentially – but not necessarily - violent outcome. The aim of this preliminary study is to identify observable criteria defining such a CS involving football fans. This focus group comprised of five experts working with football fans in the German-speaking area of Switzerland who discussed observable characteristics of a CS. Inductive content analysis led to the identification of specific criteria such as, “arrest of a fan”, “insufficient distance (<30m) between fans and police” and “fans mask themselves”. These criteria were then assigned to four phases of a CS highlighting the dynamic aspect of this phenomenon: Antecedents, Causes, Reactions, Consequence. Specifically, Causes, Reactions and Consequences are observable on site, while Antecedents include relevant, background information directly influencing a CS. This study puts forward a working definition of a CS that can facilitate the assessment of actual situations in the football context as well as for further research on fan violence prevention and control. These results also highlight similarities with studies investigating fan violence in other European countries while acknowledging unique characteristics of the Swiss German fan culture.