Andrew Vickers

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Reusability is widely suggested to be a key to improving software development productivity and quality [1,2]. It has been further argued that reuse at the requirements level can significantly increase reuse at the later stages of development [3,4]. However, there is little evidence in the literature to suggest that requirements reuse is widely practised.(More)
Organisations are seeking to improve the way they undertake engineering activities. There are numerous ways of doing this, one of which is to undertake an on-going process, or capability, enhancement activity. Praxis Critical Systems Limited provides support for such activity based primarily around the REVEAL ® requirements engineering method. By providing(More)
The traditional statistical approach to the evaluation of diagnostic tests, prediction models and molecular markers is to assess their accuracy, using metrics such as sensitivity, specificity and the receiver-operating-characteristic curve. However, there is no obvious association between accuracy and clinical value: it is unclear, for example, just how(More)
BACKGROUND Decision curve analysis (DCA) has been proposed as an alternative method for evaluation of diagnostic tests, prediction models, and molecular markers. However, DCA is based on expected utility theory, which has been routinely violated by decision makers. Decision-making is governed by intuition (system 1), and analytical, deliberative process(More)
Inconsistencies may arise in the course of specification of systems, and it is now recognised that they cannot be forbidden. Recent work has concentrated on enabling requirements descriptions to tolerate inconsistency and on proposing notations that permit inconsistency in specifications. We approach the subject by examining the use of an existing causal(More)
The design of distributed real-time systems is difficult because of the large number of issues involved with their design — inter-process communication, module structure, timing constraints, hardware constraints, reliability, etc. In this paper, we show how such issues may usefully be partitioned through the use of viewpoints before being combined together(More)
York YOl 5DD. United Kingdom. To add to the above difficulties, there are a large number ,of participants involved in the development and assessment of SCS, spanning multiple disciplines, e.g. computing, mechanical, hydro-mechanical, electronics, human factors. There are also different types of stakeholder: regulators, customers, developers, assessors,(More)
Citation for published version (APA): Vedder, M. M., de Bekker-Grob, E. W., Lilja, H., Vickers, A. J., van Leenders, G. J. L. H., Steyerberg, E. W., & Roobol, M. J. (2014). The Added Value of Percentage of Free to Total Prostate-specific Antigen, PCA3, and a Kallikrein Panel to the ERSPC Risk Calculator for Prostate Cancer in Prescreened Men. European(More)