395 research outputs found
Multimedia Explorations in Urban Policy and Planning: Beyond the Flatlands
No full textThis book explores the potential of multimedia to enrich and transform the planning field. By ‘multimedia’ the authors refer to the combination of multiple contents (both traditional and digital: texts, still images, animations, audio and video productions) and interactive platforms (offline interactive cd roms, online websites and forums, digital environments) which are opening up new possibilities in planning practice, pedagogy and research. The authors document the ways in which multimedia can expand the language of planning and the creativity of planners; can evoke the lived experience (the spirit, memories, desires) of the mongrel cities of the 21st century by engaging with stories and storytelling; and can help democratize planning processes. The diverse contributions demonstrate multimedia’s potential for layered, complex and open-ended representations of urban life; for enabling multiple forms of voice, participation and empowerment; for stimulating dialogue and influencing policy; for nurturing community engagement and community development; for expanding the horizons of qualitative and quantitative research; and for transformative learning experiences. The book conveys an excitement about the ways in which multimedia can be used by activists, immigrant and indigenous communities, planning scholars and educators, wherever urban policy and planning strategies are being debated and communities are struggling to shape, improve or protect their life spaces. But the authors go beyond enthusiasm for the new, incorporating a critical stance about the power relations embedded in these new information and communication technologies; raising questions about audience and political intentions; and outlining ethical dilemmas around authorship and ownership, collaborative processes, and the politics of voice. Leonie Sandercock is the author of eleven books, including Towards Cosmopolis: Planning for Multicultural Cities (1998) and Cosmopolis 2: Mongrel Cities of the 21st Century (2003). The latter won the Paul Davidoff Award for best book from the American Collegiate Schools of Planning. She also received the Dale Prize for community engagement (2005) and the BMW Award for Intercultural Learning (2007). Giovanni Attili is the recipient of the G. Ferraro Award for Best Urban Planning PhD Thesis in Italy in 2005. He is co-editor of Storie di Citta (2007) and author of La citta dei migranti (2008), and co-author, with Leonie Sandercock, of the book and DVD package Where Strangers become Neighbours: Integrating Immigrants in Vancouver, Canada (2009)
The third International Stroke Trial (IST-3)
No full textThe IST-3 trial is a large-scale randomised controlled trial of intravenous thrombolytic therapy of the drug Alteplase for patients with acute ischaemic stroke. The dataset includes a number of files describing the IST-3 dataset. The documentation files may be freely downloaded. The raw patient-level data files were under embargo until the 25th of January 2021 (“datashare_aug2015.sas7bdat” or “ist3.dat”); since that embargo has expired, it is no longer necessary to apply to the study investigators for access.
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The IST3 has an international trials registry ID number, which enables all the trials outputs to be linked: ISRCTN25765518
https://doi.org/10.1186/ISRCTN2576551
Supplemental material for Top 10 global educational topics in stroke: A survey by the World Stroke Organization
No full textSupplemental Material for Top 10 global educational topics in stroke: A survey by the World Stroke Organization by Monica Saini, Sarah Belson, Carmen Lahiff-Jenkins and Peter Sandercock in International Journal of Stroke</p
Updated bibliography for the IST-3 study
No full textThis is a bibliography of publications from the IST-3 trial (International Stroke Trial).
This fileset comprises two files containing the same bibliography in different formats (Word and PDF-A respectively), for accessibility. This dataset provides additional documentation for the previously-deposited dataset which contained data from the clinical trial:
Sandercock, P; Wardlaw, J; Lindley, R; Cohen, G; Whiteley, W. (2016). "The third International Stroke Trial (IST-3)", 2000-2015 [dataset]. University of Edinburgh & Edinburgh Clinical Trials Unit. https://doi.org/10.7488/ds/135
Blood markers for the diagnosis and prognosis of stroke
No full textMany blood markers have been associated with stroke. I set out to determine
whether blood markers can be applied to: (i) improve the accuracy of the clinical
diagnosis of stroke or TIA, and/or (ii) improve the prediction of poor outcome in
patients who are still symptomatic at the time of admission with stroke or TIA.
I systematically reviewed the existing literature on the diagnostic performance of a
range of blood markers measured soon after stroke onset, to inform the choice of
markers for my subsequent prospective studies in this thesis. Many studies had
deficiencies in their design, which may have explained the apparently – and
perhaps spuriously - impressive diagnostic performance of several markers. In the
light of these data I was able to improve the design of my own studies and suggest
how future studies of diagnostic markers could be improved.
In order to define an appropriate comparator test for assessing the diagnostic
accuracy of blood markers, I first examined the performance of emergency room
nurses and doctors. I assessed the accuracy of their diagnosis of TIA or stroke
(‘acute cerebrovascular disease’) in patients presenting with symptoms of suspected
stroke, and compared them with a number of stroke diagnostic scales. In the 405
patients recruited to the study, the sensitivity of emergency department staff was
77% and specificity 58%. Each stroke diagnostic scale had a slightly better
sensitivity, though worse specificity, than an emergency department clinician. I
decided to use the diagnosis by an emergency department clinician of ‘probable or
definite acute cerebrovascular disease’ as the best clinical performance reference
standard.
In blood taken from the same cohort of 405 patients, accredited research laboratories
measured markers of inflammation, thrombosis, thrombolysis, cardiac strain and
cerebral damage. Tissue plasminogen activator and loge N-terminal pro brain
natriuretic peptide were associated positively with a diagnosis of acute cerebrovascular disease, though each marker did not add diagnostic value to the
diagnosis of an emergency department doctor or nurse.
I systematically reviewed the literature examining the association between the levels
of blood markers with poor outcome (i.e. death or dependency) after stroke. I found
that although almost all markers studied had a positive association with poor
outcome, there were methodological problems with many studies, chiefly small
sample size, publication bias or within study reporting biases, and lack of
adjustment for important confounders such as age or stroke severity.
With data from the Edinburgh Stroke Study, I examined the association between
circulating markers of the inflammatory response (white cell count, interleukin-6, Creactive
protein and fibrinogen) and poor outcome after stroke. After adjustment for
age, whether the patient lived alone, was independent of activities of daily living,
was orientated, able to lift both arms and able to walk, I found that higher levels of
interleukin-6, white cell count and glucose were associated with poor outcome. The
relevant test of a biological marker is not its predictive ability alone, but whether,
when added to a validated predictive model based on clinical variables, it improves
the prediction of outcome. No individual marker improved the prediction of poor
outcome when added to a validated prognostic model based on clinical variables
alone.
From my cohort of 405 patients with suspected stroke 285 patients had a confirmed
diagnosis. Follow up of these 285 patients with confirmed acute cerebrovascular
disease showed that, after adjustment for neurological impairment and age, only
interleukin-6 and N-terminal pro brain natriuretic peptide were significantly
associated with death or disability at 3 months. Neither marker improved the
predictions of a model to predict poor outcome based on clinical variables alone.
To examine the relationship between circulating markers of the inflammatory
response and recurrent stroke, myocardial infarction, and vascular death (‘recurrent
vascular events’), again I used data from the Edinburgh Stroke Study. After adjustment for clinical predictors (age, prior MI, stroke, or TIA and AF) I found that
higher levels of interleukin-6, C-reactive protein and fibrinogen remained
significantly associated with an increased risk of recurrent vascular events.
However, the relationship with deaths from all causes was somewhat stronger for
each marker, perhaps suggesting that higher marker levels were associated with
debility rather than vascular events per se.
In conclusion, I found no marker measured could improve on the diagnostic
accuracy of an emergency department clinician for acute cerebrovascular disease,
nor improve the prediction of poor outcome by a prognostic model based upon
clinical variables. The work of this thesis does not support the routine use of blood
markers as an aid to the diagnosis of, or the prediction of outcome of, acute stroke
Magnetic resonance imaging versus computed tomography for detection of acute vascular lesions in patients presenting with stroke symptoms
No full textBackground Magnetic resonance imaging (MRI) is increasingly used for the diagnosis of acute ischaemic stroke but its sensitivity for the early detection of intracerebral haemorrhage has been debated. Computed tomography (CT) is extensively used in the clinical management of acute stroke, especially for the rapid exclusion of intracerebral haemorrhage. Objectives To compare the diagnostic accuracy of diffusion-weighted MRI (DWI) and CT for acute ischaemic stroke, and to estimate the diagnostic accuracy of MRI for acute haemorrhagic stroke. Search strategy We searched MEDLINE and EMBASE (January 1995 to March 2009) and perused bibliographies of relevant studies for additional references. Selection criteria We selected studies that either compared DWI and CT in the same patients for detection of ischaemic stroke or examined the utility of MRI for detection of haemorrhagic stroke, had imaging performed within 12 hours of stroke onset, and presented sufficient data to allow construction of contingency tables. Data collection and analysis Three authors independently extracted data on study characteristics and measures of accuracy. We assessed data on ischaemic stroke using random-effects and fixed-effect meta-analyses. Main results Eight studies with a total of 308 participants met our inclusion criteria. Seven studies contributed to the assessment of ischaemic stroke and two studies to the assessment of haemorrhagic stroke. The spectrum of patients was relatively narrow in all studies, sample sizes were small, there was substantial incorporation bias, and blinding procedures were often incomplete. Amongst the patients subsequently confirmed to have acute ischaemic stroke (161/226), the summary estimates for DWI were: sensitivity 0.99 (95% CI 0.23 to 1.00), specificity 0.92 (95% CI 0.83 to 0.97). The summary estimates for CT were: sensitivity 0.39 (95% CI 0.16 to 0.69), specificity 1.00 (95% CI 0.94 to 1.00). The two studies on haemorrhagic stroke reported high estimates for diffusion-weighted and gradient-echo sequences but had inconsistent reference standards. We did not calculate overall estimates for these two studies. We were not able to assess practicality or cost-effectiveness issues. Authors' conclusions DWI appears to be more sensitive than CT for the early detection of ischaemic stroke in highly selected patients. However, the variability in the quality of included studies and the presence of spectrum and incorporation biases render the reliability and generalisability of observed results questionable. Further well-designed studies without methodological biases, in more representative patient samples, with practicality and cost estimates are now needed to determine which patients should undergo MRI and which CT in suspected acute stroke
International Stroke Trial database (version 2)
No full textThe International Stroke Trial (IST) was one of the biggest randomised trials in acute stroke. Methods: Available data on variables assessed at randomisation, at the early outcome point (14-days after randomisation or prior discharge) and at 6-months were extracted and made publically available. Results and Conclusions: The IST provides an excellent source of primary data easy-to-use for sample size calculations and preliminary analysis necessary for planning a good quality trial.
# Associated publications #
* The erratum paper explains the difference between this version ie version 2, and the previous version: Sandercock, P.A.G., Niewada, M., Członkowska, A. et al. Erratum to: The International Stroke Trial database. Trials 13, 24 (2012). https://doi.org/10.1186/1745-6215-13-24 .
* Main results paper for the trial: International Stroke Trial Collaborative Group 1997, 'The International Stroke Trial (IST): A randomised trial of aspirin, subcutaneous heparin, both, or neither among 19 435 patients with acute ischaemic stroke', The Lancet, vol. 349, no. 9065, pp. 1569-1581. https://doi.org/10.1016/S0140-6736(97)04011-7 .International Stroke Trial database unicode data file
International Stroke Trial database csv data fil
Mechanisms of Degradation and Identification of Connectivity and Erosion Hotspots
No full textThe context of processes and characteristics of soil erosion and land degradation in Mediterranean lands is outlined. The concept of connectivity is explained. The remainder of the chapter demonstrates development of methods of mapping, analysis and modelling of connectivity to produce a spatial framework for development of strategies of use of vegetation to reduce soil erosion and land degradation. The approach is applied in a range of typical land use types and at a hierarchy of scale from land unit to catchment. Patterns of connectivity and factors influencing the location and intensity of processes are identified, including the influence of topography, structures such as agricultural terraces and check dams, and past land uses. Functioning of connectivity pathways in various rainstorms is assessed. Modes of terrace construction and extent of maintenance, as well as presence of tracks and steep gradients are found to be of importance. A method of connectivity modelling that incorporates effects of structure and vegetation was developed and has been widely applied subsequently
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