Bayesian value-of-infomation analysis: an application to a policy model of Alzheimer's disease

A framework is presented that distinguishes the conceptually separate decisions of which treatment strategy is optimal from the question of whether more information is required to inform this choice in the future. The authors argue that the choice of treatment strategy should be based on expected utility, and the only valid reason to characterize the uncertainty surrounding outcomes of interest is to establish the value of acquiring additional information. A Bayesian decision theoretic approach is demonstrated through a probabilistic analysis of a published policy model of Alzheimer’s disease. The expected value of perfect information is estimated for the decision to adopt a new pharmaceutical for the population of patients with Alzheimer’s disease in the United States. This provides an upper bound on the value of additional research. The value of information is also estimated for each of the model inputs. This analysis can focus future research by identifying those parameters where more precise estimates would be most valuable and indicating whether an experimental design would be required. We also discuss how this type of analysis can also be used to design experimental research efficiently (identifying optimal sample size and optimal sample allocation) based on the marginal cost and marginal benefit of sample information. Value-of-information analysis can provide a measure of the expected payoff from proposed research, which can be used to set priorities in research and development. It can also inform an efficient regulatory framework for new healthcare technologies: an analysis of the value of information would define when a claim for a new technology should be deemed substantiated and when evidence should be considered competent and reliable when it is not cost-effective to gather any more information

Priority setting for research in health care: An application of value of information analysis to glycoprotein IIb/IIIa antagonists in non-ST elevation acute coronary syndrome

The purpose of this study is to explain the rationale for the value of information approach to priority setting for research and to describe the methods intuitively for those familiar with basic decision analytical modeling. A policy-relevant case study is used to show the feasibility of the method and to illustrate the type of output that is generated and how these might be used to frame research recommendations. The case study relates to the use of glycoprotein IIb/IIIa antagonists for the treatment of patients with non-ST elevation acute coronary syndrome. This is an area that recently has been appraised by the National Institute for Health and Clinical Excellence

Design management of sustainable fashion

The aim of this research is to advance an understanding of how design in the fashion industry can be successfully managed to contribute to environmental sustainability. Its objectives are to investigate how fashion businesses establish and support environmentally sustainable strategies, and how design leaders and managers contribute to the setting of these goals. The paper reviews the literature of the fashion industry, its sustainability strategies, and the management of design. Semi-structured interviews and a quantitative survey of designers was undertaken in the UK. A framework based on the level of business engagement in sustainability was used to structure the thematic analysis of the findings. The research demonstrates the relatively weak influence of designers on sustainable fashion strategy and concludes by developing design management theory for sustainability through a modified Design Atlas framework

First-Principles Calculation of Electric Field Gradients and Hyperfine Couplings in YBa2Cu3O7

The local electronic structure of YBa2Cu3O7 has been calculated using first-principles cluster methods. Several clusters embedded in an appropriate background potential have been investigated. The electric field gradients at the copper and oxygen sites are determined and compared to previous theoretical calculations and experiments. Spin polarized calculations with different spin multiplicities have enabled a detailed study of the spin density distribution to be made and a simultaneous determination of magnetic hyperfine coupling parameters. The contributions from on-site and transferred hyperfine fields have been disentangled with the conclusion that the transferred spin densities essentially are due to nearest neighbour copper ions only with marginal influence of ions further away. This implies that the variant temperature dependencies of the planar copper and oxygen NMR spin-lattice relaxation rates are only compatible with commensurate antiferromagnetic correlations. The theoretical hyperfine parameters are compared with those derived from experimental data.Comment: 14 pages, 12 figures, accepted to appear in EPJ

Extending clothing lifetimes: an exploration of design and supply chain challenges

The environmental impact of clothing could be reduced if average garment lifetimes were increased. The paper explores the design and supply chain implications of clothing longevity, adapting models from sustainable clothing design research, and evidence from interviews and expert roundtables. The research concludes that the process of design for longevity could be adopted by clothing retailers and brands, but that the principles behind adopting this strategy lack credence in industry, because the mandate to do so, and robust business models, are lacking. The paper identifies a range of conflicting priorities between commercial and sustainable practice that must be addressed to reduce the environmental impact of clothing by extending its useful life, and makes recommendations for industry and future research. However, the limitations to adopting more sustainable practice relate to fashion and market segment, are systemic within the clothing supply chain and attempts to resolve these require a commercial imperative

Bayesian Value-of-Information Analysis: An Application to a Policy Model of Alzheimer's Disease

A framework is presented which distinguishes the conceptually separate decisions of which treatment strategy is optimal from the question of whether more information is required to inform this choice in the future. The authors argue that the choice of treatment strategy should be based on expected utility and the only valid reason to characterise the uncertainty surrounding outcomes of interest is to establish the value of acquiring additional information. A Bayesian decision theoretic approach is demonstrated though a probabilistic analysis of a published policy model of Alzheimer’s disease. The expected value of perfect information is estimated for the decision to adopt a new pharmaceutical for the population of US Alzheimer’s disease patients. This provides an upper bound on the value of additional research. The value of information is also estimated for each of the model inputs. This analysis can focus future research by identifying those parameters where more precise estimates would be most valuable, and indicating whether an experimental design would be required. We also discuss how this type of analysis can also be used to design experimental research efficiently (identifying optimal sample size and optimal sample allocation) based on the marginal cost and marginal benefit of sample information. Value-of-information analysis can provide a measure of the expected payoff from proposed research, which can be used to set priorities in research and development. It can also inform an efficient regulatory framework for new health care technologies: an analysis of the value of information would define when a claim for a new technology should be deemed “substantiated” and when evidence should be considered “competent and reliable” when it is not cost-effective to gather anymore information.stochastic CEA; Bayesian decision theory; value of information.

From rag trade to retail: garment failure and the potential for sustainable fashion

Around 1.8 million tonnes of clothing waste is generated annually in the UK, accounting for around 5% of total UK household waste, with the lifetime of many garments unduly short. As a result of greater attention being placed on waste reduction at European Union and national government level, however, interest in the potential for increased garment lifetimes has grown in recent years and, despite obvious tensions between fashion and longevity, retailers have begun to engage in the debate. This paper presents findings from a research project undertaken for WRAP (Waste and Resources Action Programme) aimed at an industry-supported approach to measuring, specifying and communicating aspects of clothing longevity. Although a high proportion of garments are thrown away in wearable condition, many of which are reused, others are discarded because they are damaged or worn out. This study was concerned with the latter. Although a literature review identified recent studies addressing the context surrounding the fashion industry and elements of the ‘fast fashion’ debate, providing some explanation for the disposable nature of much fashion, no primary research relating to garment failure was found. A visual survey of discarded clothing was thus undertaken in order to increase knowledge and understanding of reasons for garment failure. Visits were made to three UK based textile reuse and recycling organisations. Around 1,500 discarded garments in a failed condition were subject to a systematic analysis, categorised by type of garment and condition and with visual images recorded. Only garments no longer ‘fit for purpose’, deemed not to be in a good enough condition to be re-sold in the UK, were assessed. The method of first hand observation enabled consideration of why items had been discarded and had the benefit of being less subjective and not dependent upon the memory of people who had disposed of them. The main reasons why garments appeared to have been discarded were identified as colour fading and problems relating to fabric quality such as pilling of knitted items and fabric breakdown in the form of fraying and thinning. Other key issues were general wear around the crotch of trousers and jeans, discolouration in white shirts and holes in seams. The detailed findings, presented by type of garment and type of fabric, will be useful to fashion retailers and brands wishing to respond to growing concerns about waste arising from short-lived clothing. It should enable them to review their performance criteria and testing procedures in order to adjust garment specifications, and to market garments appropriately

Product development and supply: help or hindrance to clothing longevity?

Designing longer lasting clothing helps to reduce unsustainable levels of product disposal and subsequent waste. This has led to a call for retailers to enhance clothing longevity, supported by new business models to reduce any impact on competitiveness. While some research suggests that a significant proportion of consumers would buy longer lasting clothes, this view is not necessarily accepted by industry strategists. This paper, which reports on research undertaken for WRAP (Waste and Resources Action Programme), explores conflicting priorities between commercial and sustainable practice, and problematic trade-offs in the supply chain between commercial, technical and design aspects of reducing the environmental impact of clothing. The study adopted a mixed methodology, incorporating qualitative interviews and a survey, and encompasses views of retailers, manufacturers and suppliers from different segments of the UK fashion market. The findings confirm that retailers and brands drive the new product development process and set standards for their supply chains, but globalization, product churn and testing regimes challenge the critical path schedule. Although current tests confirm product quality (WRAP, 2013), there is a perception within industry that designing for longevity increases testing, inflating the risk of failure and extending lead-times, resulting in a mismatch between cost, time and longevity priorities that limits adoption of design for longevity. Meanwhile, clothing longevity is not perceived to add value for many consumers and therefore is not prioritised. While it is technically possible to enhance clothing longevity, the findings demonstrate empirically that this deviates from current commercial drivers of global clothing supply chains. By combining different perspectives on supply chains, new product development and sustainability, inherent conflicts are revealed

Interdisciplinary educational approaches to clothing longevity

How do we encourage and enable interdisciplinary systems thinking approaches to sustainable fashion design and business education? In preparation for a workshop at the 2017 PLATE conference, this paper introduces the context of a toolkit – The Clothing Durability Dozen (Cooper at al, 2016b) – aimed at enabling students to collaborate and learn about clothing longevity across disciplines and creating a better understanding of the roles that different departments can play in placing sustainable design strategies at the heart of the clothing industry. In line with education for sustainable development (ESD) principles, objectives include stimulating learning and promote core competencies, such as critical and systemic thinking, collaborative decision-making, and taking responsibility for present and future generations. In the workshop, participants will trial and contribute to the development of the toolkit and any necessary supporting material, the final version of which will be available for use as an educational tool

Opportunities and challenges of new product development and testing for longevity in clothing

Many types of clothing are now seen as disposable by consumers in the UK even though durability is among the top criteria that consumers claim to use when buying garments (WRAP, 2012). Routine tests for clothing performance carried out by retailers are generally designed to ensure garments are 'fit for purpose', not to establish durability or longevity. Designing clothing that lasts longer is, however, key to reducing waste and has become a government policy objective (Defra, 2011). This paper discusses the findings from a recent research project, carried out for WRAP (Waste and Resources Action Programme), that investigated the opportunities for measuring, specifying and communicating aspects of clothing longevity within a Longevity Protocol. The Protocol is intended to enable retailers to obtain a reliable indication of garment life expectancy and was piloted in conjunction with clothing industry practitioners. It incorporates recommendations for best practice in product development and a testing regime that provides an indication of garment life expectancy (WRAP, 2014). Overall, the findings from the pilot suggest that it is possible to test for garment longevity, however, this process can be drawn-out and may not fit easily into the normal product development process. Furthermore, variations in consumer wearing patterns and laundering make it difficult for retailers to guarantee and communicate product lifetimes in absolute terms. The research adds to a growing body of evidence that supports the concept of design for clothing longevity. The findings will help to inform strategies for the implementation of government policy on sustainable clothing, but point to the need for refined testing processes to support this agenda