A predictive Bayesian approach to risk analysis in health care

<p>Abstract</p> <p>Background</p> <p>The Bayesian approach is now widely recognised as a proper framework for analysing risk in health care. However, the traditional text-book Bayesian approach is in many cases difficult to implement, as it is based on abstract concepts and modelling.</p> <p>Methods</p> <p>The essential points of the risk analyses conducted according to the predictive Bayesian approach are identification of observable quantities, prediction and uncertainty assessments of these quantities, using all the relevant information. The risk analysis summarizes the knowledge and lack of knowledge concerning critical operations and other activities, and give in this way a basis for making rational decisions.</p> <p>Results</p> <p>It is shown that Bayesian risk analysis can be significantly simplified and made more accessible compared to the traditional text-book Bayesian approach by focusing on predictions of observable quantities and performing uncertainty assessments of these quantities using subjective probabilities.</p> <p>Conclusion</p> <p>The predictive Bayesian approach provides a framework for ensuring quality of risk analysis. The approach acknowledges that risk cannot be adequately described and evaluated simply by reference to summarising probabilities. Risk is defined by the combination of possible consequences and associated uncertainties.</p

Managing Exposure to Pipeline’s Risks: Improving Brazil’s Risk-Based Regulatory Process

Traditional risk-based decision-making processes have limitations that often compromise the management of technological hazards. The research is organized into three major components. Firstly, it investigates concepts and thinking outside the literature on risk regulation that offer opportunities to improve risk-based processes, such as governance and risk governance, environmental and social justice, vulnerability, resilience, complex systems, ethics, and the precautionary principle. Secondly, identified opportunities to improve risk-based approaches are assessed in the context of the Brazilian environmental licensing process for gas and oil transmission pipelines. The Brazilian case study is explored through interviews and surveys with thirty-two key stakeholders, aimed at describing and understanding the situation. Finally, it is discussed how the implications of the proposed conceptual framework and findings from the case study contribute to the theoretical perspectives on technological risk regulation. The research advocates that (1) regulatory processes for technological hazards need to effectively incorporate ‘human systems’ into their routines as a way to become more holistic; (2) decision-making processes need to strengthen the transition from assessment of risks to management of exposure; (3) regulators need to shift focus to the management of exposure as opposed to the current facility-centered management of risks; (4) this transition is facilitated if the regulatory process has an independent routine for management; and (5) a resilience plan, encompassing components from risk management and land-use planning, articulates the interaction between people and hazardous facilities, that share a common space, towards better practices to effectively manage exposure to risks. Considering these five points, the research suggests an adaptation of the Risk Governance Model for the regulation of hazardous linear installations

Utilizing Knowledge Transfer to Promote Management of Countervailing Risks in Value Stream Analysis

Organizations are frequently faced with the challenges of modifying and streamlining their processes by utilizing the latest process improvement techniques such as Lean Thinking. They use these techniques to allow them to better perform their organizational purposes through the elimination of waste and non-value added steps. Personnel performing these modifications need to account for potential outcomes and risks when streamlining processes. An association of knowledge transfer and experience to the identification and handling of these countervailing or alternative risks when performing Lean Thinking value stream analysis is investigated. The elements of risk management, Lean Thinking and knowledge transfer are described. This dissertation presents the results of a non-experimental examination to identify knowledge transfer as a means to promote management of countervailing risks that may arise when performing Value Stream Analysis and provides a foundation for future research. A research model was formulated, and a survey instrument developed with data collected from Department of the Navy personnel during Lean Thinking events. Quantitative data analysis supported the research question and showed an association between a decision-maker\u27s knowledge from other projects and the identification and handling of countervailing risks that arise during Value Stream Analysis

Characterization, Coordination, and Legitimization of Risk in Cross-Disciplinary Situations

In contemporary times, policy makers and risk managers find themselves required to make decisions about how to prevent or mitigate complex risks that face society. Risks, such as global warming and energy production, are considered complex because they require knowledge from multiple scientific and technical disciplines to explain the mechanisms that cause and/or prevent hazards. This dissertation focuses on these types of situations: when experts from different disciplines and professions interact to coordinate and legitimize risk characterizations. A review of the risk communication literature highlights three main critiques: (1) Risk communication research historically treats expert groups as uniform and does not consider the processes by which they construct and legitimize risk understandings. (2) Risk communication research tends to privilege transmissive and message-centered approached to communication rather than examine the discursive management and coordination of different risk understandings. (3) Rather than assuming the taken-for-granted position that objective scientific knowledge is the source of legitimacy for technical risk understandings, risk communication research should examine the way that expert groups legitimate their knowledge claims and emphasize the transparency of norms and values in public discourse. This study performs an in-depth analysis of the case of cesium chloride. Cesium chloride is a radioactive source that has several beneficial uses medical, research, and radiation safety applications. However, it has also been identified as a security threat due to the severity of its consequences if used in a radiological dispersal device, better known as a “dirty bomb.” A recent National Academy of Sciences study recommended the replacement or elimination of cesium chloride sources. This case is relevant to the study of risk communication among multidisciplinary experts because it involves a wide variety of fields to discuss and compare terrorism risks and health risks. This study uses a multi-perspectival framework based on Bakhtin’s dialogism that enables entrance into the discourse of experts’ risk communication from different vantage points. Three main implications emerge from this study as seen through the lens of dialogism. (1) Expert risk communication in cross-disciplinary situations is a tension-filled process. (2) Experts who interact in cross-disciplinary situations manage the tension between discursive openness and closure through the use of shared resources between the interpretative repertoires, immersion and interaction with other perspectives, and the layering of risk logics with structural resources. (3) The emergence of security risk Discourse in a post-9/11 world involves a different set of resources and strategies that risk communication studies need to address. In the case of cesium chloride issue, the interaction of experts negotiated conflict about the characterization of this isotope as a security threat or as being useful and unique. Even though participants and organizations vary in how they characterize cesium chloride, most maintained some level of balance between both characterizations—a balance that was constructed through their interactions with each other. This project demonstrates that risk characterizations risks shape organizational decisions and priorities in both policy-making and regulatory organizations and private-sector and functional organizations

Formalised approach to the management of risk

Taking a pragmatic, systems engineering approach, this thesis identifies a number of fundamental issues that presently arise in risk management, primarily as a result of the overly complex and somewhat outdated approach conventionally taken in process definition and a lack of coherence within the current risk management vocabulary. It is suggested that many recent developments in systems engineering have largely been ignored by the risk management community. The objective of this work is to develop a formalised approach to the management of risk using a model based approach this will enable a fundamental simplification of the risk management process, resulting - amongst other things - in an improved understanding of the associated terminology. An object oriented modelling approach, now widely exploited in systems engineering, has been used to provide an insight into many existing risk management standards considering the approaches they present and terminology used. It has also been used to derive both a set of processes for risk management and a methodology for implementation. Alongside this, a consistent, inter-related terminology as been proposed for use with these processes. The outcome of this work is a formalised but pragmatic approach to risk management including the definition of processes, ontology for risk management and a pragmatic methodology for the application of the processes. This approach has been validated in a number of case studies of varying depth and breadth, covering health &amp; safety, business, project and individual needs, showing that the proposed processes and terminology can be used effectively in different organisations and industries.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Extension of Quantitative Risk Assessment to the Analysis of External Hazard Factors in the Chemical and Process Industry

The PhD research project is aimed at developing and applying an innovative framework toward Risk Assessment of cascading events within the chemical and process industry, addressing both domino and security-based events. Cascading events are catastrophic accidents, triggered by external hazard factors, including safety-based (i.e., domino) and security-based events. In the chemical industry domain, barriers provide a crucial role for the prevention, control and mitigation of cascading events. Therefore, it is necessary to apply innovative techniques, aimed at the evaluation of barriers technical performance and at their optimal economic allocation, to be inserted within Quantitative Risk Assessment (i.e., QRA). Concerning barriers technical performance, the research activity is aimed at applying Bayesian Networks to safety barriers performance assessment, regarding domino events. Starting from a conventional approach, preliminary applications have been aimed at implementing a Bayesian approach to barriers performance assessment concerning major accidents. Therefore, the approach has been extended to domino accident analysis, in purpose to evaluate the effect of barriers introduction within modelling. The case studies demonstrated that the application of a Bayesian approach provides a very accurate barriers performance assessment within QRA, with reference to external hazard factors driven accidents (i.e., domino events), offering a realistic risk picture. Concerning barriers optimal economic allocation, the research activity is aimed at developing and applying an original economic model for the prevention of security-based cascading events. The model includes security upgrades performance and costs assessment, evaluation of benefits and definition of threat and vulnerability probabilities. The application of economic techniques, by means of cost-benefit and cost-effectiveness analyses, enables barriers optimal allocation within budgets constraints. Validation of the model is provided by application to relevant case studies. Therefore, the model enables defining rational criteria for barriers optimal selection and allocation and its outputs support the inclusion of security hazards within QRA, and related decision-making

Développement de trois éléments d'une méthodologie de gestion du risque de portefeuilles de projets

La gestion du risque joue un rôle très important dans la gestion d’un portefeuille de projets. Un portefeuille est constitué par un choix judicieux de projets dont le niveau de risque est acceptable. Le choix de projets est fait également de manière à maximiser la valeur du portefeuille. Les concepts de maximisation de la valeur et d’équilibrage risque-bénéfice sont des concepts fondamentaux dans la théorie de la gestion de portefeuilles. Voici l’importance d’avoir une gestion du risque qui permet de maintenir un niveau acceptable du risque et de maximiser la valeur du portefeuille en cherchant à exploiter les opportunités. La recherche réalisée a permis l’élaboration de trois éléments d’une méthodologie de gestion du risque conçue spécifiquement pour être appliquée durant la gestion de portefeuilles de projets. Les trois éléments considèrent les décisions prises durant les processus de la gestion de portefeuilles ainsi que les caractéristiques du portefeuille dans une approche stratégique. Ils mettent en valeur la recherche d’opportunités et leur maximisation. Spécifiquement, les éléments développés sont : une démarche d’identification de risques et d’opportunités, un ensemble d’indicateurs clé de performance et une démarche pour construire et utiliser une matrice de suivi des risques et des opportunités. Ces éléments peuvent être facilement intégrés aux méthodologies génériques ou aux standards acceptés de gestion du risque. Les éléments n’invalident pas les concepts existants dans la littérature. Au contraire, ils complètent la théorie déjà existante de gestion du risque en tenant compte des apports d’autres chercheurs. Cette recherche met en évidence les relations existantes entre les objectifs du portefeuille et les projets. Ces relations forment un réseau d’interdépendances. Plus spécifiquement, ces interdépendances sont composées par les objectifs, les bénéfices et les projets. Une fois que ces composants sont situés dans le temps, ils forment les flux « projets-bénéfice-objectifs ». Cette façon de présenter les concepts est d’une grande utilité puisqu’elle permet de chercher les conséquences sur l’atteinte des objectifs. Elle permet également d’établir des marges de manœuvre pour réagir afin de minimiser ou de maximiser les conséquences. Des plans d’action sont mis en place depuis la détection des premiers risques ou des premières opportunités matérialisées. Cela fournit un caractère anticipatif qui facilite l’adaptation du portefeuille aux conditions changeantes de son environnement.----------ABSTRACT Risk management plays an important role in managing a portfolio of projects. The reason for having a portfolio of projects is the maximization of the portfolio value following a selection of projects under an accepted level of risk. The concepts of value maximization and risk-benefit balancing are fundamental concepts in the theory of portfolio management. This is the importance of risk management which maintains an acceptable level of risk and maximizes the portfolio value searching and increasing opportunities. The research conducted has had as result the development of three elements of a risk management methodology which is specifically designed for the management of project portfolios. The three developed elements consider decisions taken during the processes of portfolio management; they also consider portfolio characteristics from a strategic standpoint. They highlight the research of opportunities as well as their maximization. Specifically, the developed elements are: a structure for identifying risks and opportunities, a set of key strategic performance indicators, and a framework for building and using a matrix to monitor risks and opportunities. These elements can be easily integrated within generic methodologies or accepted standards of risk management. The elements do not invalidate existing concepts in the literature. In opposite, they complement existing theory of risk management adding concepts found in the literature and considered as a need by other researchers. Research has revealed the existing relationships between portfolio objectives and projects which form a network of interdependences. These interdependences are built from objectives, benefits and projects; once these components are extended on a time scale, they form flows of "projects-profit-objectives." This way of exhibiting those concepts is very useful because it allows for searching the impact on the achievement of objectives. At the same time, they allow for setting the manoeuvre margin to react and minimizing or maximizing consequences. Action plans are put in place since the first detection of materialized risks or opportunities. It provides an anticipatory characteristic which helps adapt the portfolio to changing conditions in which the portfolio progresses. The research has explored several concepts, such as benefits management, key performance indicators, critical success factors, and the complexity of a project portfolio. It has also explored current guides and methodologies in order to establish a framework within which the developed elements would be integrated

Riesgo percibido en la construcción: Un estudio cross cultural

La presente Tesis Doctoral ha sido realizada dentro del Departamento de Construcciones Arquitectónicas II de la Universidad de Sevilla. Es un estudio cross-cultural acerca del riesgo percibido en la construcción. Se ha realizado en España, Perú y Nicaragua. Es un estudio exploratorio transversal mediante cuestionarios que se basa en el paradigma psicométrico (Fischhoff et al., 1978). Así, se ha pretendido un acercamiento a la explicación del concepto de riesgo percibido en el lugar de trabajo desde distintas perspectivas. Para poder explicar las diferencias culturales que pudieran emerger se ha utilizado el enfoque de Hofstede (1980, 1999) el cual explica la cultura en función de 5 dimensiones principalmente. A continuación se exponen los principales resultados. En primer lugar se ha hallado un patrón o perfil del riesgo percibido muy parecido para los tres países de estudio. Es una conclusión muy interesante ya que implica que los distintos atributos del riesgo han sido puntuados de forma similar en países de diferentes áreas geográficas del planeta. Se sugiere que este gráfico puede ser un modelo que sigan los sujetos en otros países. Por otro lado, los análisis de regresión demuestran que el riesgo percibido en el trabajo es explicado con una alta varianza por (1) el atributo relacionado con la gravedad de las consecuencias en caso de producirse un riesgo y (2) con la demora de las consecuencias, también en caso de materializarse un riesgo. En menor medida también explican la varianza el atributo relacionado con (3) la probabilidad de que se produzca el riesgo y (4) el potencial catastrófico derivado del riesgo. Los análisis cluster realizados también han hecho emerger conglomerados en función de estos atributos. Por lo que se puede concluir que estos cuatro atributos son los más importantes de los nueve considerados por Fischhoff et al. (1978) en relación a la actividad laboral de los sujetos. Con respecto a las variables personales que pueden afectar al riesgo percibido del trabajador, se ha concluido que sólo la formación del trabajador afecta a su percepción a nivel de muestra global. Con respecto al análisis cultural y su relación con el riesgo percibido, puede concluirse lo siguiente: todas las dimensiones de este estudio han sido acordes con los resultados mostrados en los estudios originales de Hofstede (teniendo en cuenta las holguras que se deben contemplar para este tipo de resultados), excepto la dimensión que explora el individualismo vs colectivismo. En esta dimensión se ha detectado una homogeneización considerable entre los tres países (España y Perú estaban en el estudio original de Hofstede; Nicaragua no) presentando resultados muy similares. Esto puede deberse a los avances en los medios de comunicación y sobretodo en la globalización que subyace en el uso de internet. En cuanto a su relación con el riesgo percibido, las dimensiones relativas al individualismo vs colectivismo y a la distancia al poder no presentan ningún aporte en cuanto a la explicación del riesgo percibido en los tres países. Sin embargo, la dimensión que explora la aversión al riesgo, sí ayuda a explicar por qué se percibe de forma diferente el riesgo. En la dimensión relativa a la orientación a corto plazo vs orientación a largo plazo, la muestra española ha basado sus decisiones en lo que pueda ocurrir a largo plazo debido a aspectos culturales que hacen variar el riesgo percibido. No ocurre lo mismo en los otros dos países

A formalised approach to the management of risk

Taking a pragmatic, systems engineering approach, this thesis identifies a number of fundamental issues that presently arise in risk management, primarily as a result of the overly complex and somewhat outdated approach conventionally taken in process definition and a lack of coherence within the current risk management vocabulary. It is suggested that many recent developments in systems engineering have largely been ignored by the risk management community. The objective of this work is to develop a formalised approach to the management of risk using a model based approach this will enable a fundamental simplification of the risk management process, resulting - amongst other things - in an improved understanding of the associated terminology. An object oriented modelling approach, now widely exploited in systems engineering, has been used to provide an insight into many existing risk management standards considering the approaches they present and terminology used. It has also been used to derive both a set of processes for risk management and a methodology for implementation. Alongside this, a consistent, inter-related terminology as been proposed for use with these processes. The outcome of this work is a formalised but pragmatic approach to risk management including the definition of processes, ontology for risk management and a pragmatic methodology for the application of the processes. This approach has been validated in a number of case studies of varying depth and breadth, covering health &amp; safety, business, project and individual needs, showing that the proposed processes and terminology can be used effectively in different organisations and industries