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Conventional Assessment (conventional + assessment)

Distribution by Scientific Domains

Medical Sciences	60%

Selected Abstracts

Clinical impact of, and prognostic stratification by, F-18 FDG PET/CT in head and neck mucosal squamous cell carcinoma

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2007
Caroline A. Connell FRANZCR
Abstract Background The aim of this study was to determine prospectively the incremental value of positron emission tomography/computed tomography (PET/CT) over conventional assessment (clinical examination and CT/MRI imaging). Methods All patients undergoing 18F-fluorodeoxyglucose (FDG)-PET/CT for primary head and neck mucosal squamous cell carcinoma between January 2002 and December 2003 (inclusive) were included in this study provided they had undergone contemporaneous conventional assessment of the head and neck region and had 12 months minimum follow-up. Results Seventy-six patients underwent 100 PET/CT scans. The majority of patients (74%) were treated with definitive (chemo)radiotherapy. Median follow-up time was 28 months. PET/CT led to a TNM classification alteration in 34% (12/35), a change in radiotherapy planning technique and/or dose in 29% (10/35), and altered treatment response assessment in 43% (13/30). A complete metabolic response was predictive of overall survival (p = .037). Conclusion Our results support incorporation of PET/CT into the management paradigm of head and neck mucosal squamous cell carcinoma. © 2007 Wiley Periodicals, Inc. Head Neck 2007 [source]

Use and performances of Web-based portfolio assessment

BRITISH JOURNAL OF EDUCATIONAL TECHNOLOGY, Issue 2 2009
Chi-Cheng Chang
This research explored the influence of a Web-based portfolio assessment system on students' performances. The methodological procedure adopted was to have the experimental group use the system, with the control group using conventional assessment. The study subjects were junior high school students of two computer classes. The experimental results revealed that the use of the system has significant positive influence on students' performances. According to estimated effect size, the most significant indicators were reflection, self-assessment, continuous improvement, goal setting, problem solving, data gathering, work and peer interaction. However, peer-assessment performance was not enhanced significantly. Therefore, one recommendation was to reduce peer-assessment and instead offer specific illustrations to the students as well as the opportunity to drill. [source]

Prospective comparison of [18F]fluorodeoxyglucose positron emission tomography with conventional assessment by computed tomography scans and serum tumor markers for the evaluation of residual masses in patients with nonseminomatous germ cell carcinoma

CANCER, Issue 9 2002
Christian Kollmannsberger M.D.
Abstract BACKGROUND To assess the ability of [18F]fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET) to predict the viability of residual masses after chemotherapy in patients with metastatic nonseminomatous germ cell tumors (GCT), PET results were compared in a blinded analysis with computed tomography (CT) scans and serum tumor marker changes (TUM) as established methods of assessment. METHODS Independent reviewers who were blinded to each other's results evaluated the PET results and corresponding CT scan and TUM results in 85 residual lesions from 45 patients. All patients were treated within prospective clinical trials and received primary/salvage, high-dose chemotherapy with autologous blood stem cell support for primary poor prognosis disease or recurrent disease. PET results were assessed both visually and by quantifying glucose uptake (standardized uptake values). Results were validated either by histologic examination of a resected mass and/or biopsy (n = 28 lesions) or by a 6-month clinical follow-up after evaluation (n = 57 lesions). RESULTS F-18 FDG PET showed increased tracer uptake in 32 of 85 residual lesions, with 29 true positive (TP) lesions and three false positive (FP) lesions. Fifty-three lesions were classified by PET as negative (no viable GCT), 33 lesions were classified by PET as true negative (TN), and 20 lesions were classified by PET as false negative (FN). In the blinded reading of the corresponding CT scan and TUM results, 38 residual lesions were assessed correctly as containing viable carcinoma and/or teratoma. Forty-six lesions were classified as nonsuspicious by CT scan/TUM (33 TN lesions and 14 falsely classified lesions). PET correctly predicted the presence of viable carcinoma in 5 of these 14 and the absence of viable carcinoma in 3 of these 14 lesions. Resulting sensitivities and specificities for the prediction of residual mass viability were as follows: PET, 59% sensitivity and 92% specificity; radiologic monitoring, 55% sensitivity and 86% specificity; and TUM, 42% sensitivity and 100% specificity. The positive and negative predictive values for PET were 91% and 62%, respectively. The diagnostic efficacy of PET did not improve when patients with teratomatous elements in the primary tumor were excluded from the analysis. In patients with multiple residual masses, a uniformly increased residual F-18 FDG uptake in all lesions was a strong predictor for the presence of viable carcinoma. CONCLUSIONS F-18 FDG PET imaging performed in conjunction with conventional staging methods offers additional information for the prediction of residual mass histology in patients with nonseminomatous GCT. A positive PET is highly predictive for the presence of viable carcinoma. Other useful indications for a PET examination include patients with multiple residual masses and patients with marker negative disease. Cancer 2002;94:2353,62. © 2002 American Cancer Society. DOI 10.1002/cncr.10494 [source]

Science, systems and geomorphologies: why LESS may be more

EARTH SURFACE PROCESSES AND LANDFORMS, Issue 9 2008
Keith Richards
Abstract This paper has been stimulated by a debate triggered by the then British Geomorphological Research Group (now the British Society for Geomorphology) about the connections between geomorphology and Earth system science (ESS). Its purpose is to expand on some arguments we have already made about these connections, amongst other things drawing attention to neglected historical antecedents, and to the questionable status of the science implied by ESS. A premise of this further paper is that such a debate cannot be assumed to mirror conventional assessments of the content of a science, since it is about scientific institutional structures, names, boundaries and relationships. This implies that the terms of reference go well beyond critical scientific appraisal, extending to matters of evaluating a social organization, and to politics, policies, purposes and practices. We therefore begin by considering the sociology of science, scientific knowledge and technology, before moving to a consideration of the historical relationship amongst geomorphology, geology and physical geography; and to some perspectives this might offer for the current debate. Epistemological issues, arising both from the use of systems theory over multiple spatial and temporal scales, and from the demands of contemporary environmental science, are then introduced, and these lead to a conclusion that geomorphology might more appropriately be assessed against (or seen as part of) a more locally orientated ESS, which we term LESS. Copyright © 2008 John Wiley & Sons, Ltd. [source]