879 resultados para fidelity encouragement


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Most unsignalised intersection capacity calculation procedures are based on gap acceptance models. Accuracy of critical gap estimation affects accuracy of capacity and delay estimation. Several methods have been published to estimate drivers’ sample mean critical gap, the Maximum Likelihood Estimation (MLE) technique regarded as the most accurate. This study assesses three novel methods; Average Central Gap (ACG) method, Strength Weighted Central Gap method (SWCG), and Mode Central Gap method (MCG), against MLE for their fidelity in rendering true sample mean critical gaps. A Monte Carlo event based simulation model was used to draw the maximum rejected gap and accepted gap for each of a sample of 300 drivers across 32 simulation runs. Simulation mean critical gap is varied between 3s and 8s, while offered gap rate is varied between 0.05veh/s and 0.55veh/s. This study affirms that MLE provides a close to perfect fit to simulation mean critical gaps across a broad range of conditions. The MCG method also provides an almost perfect fit and has superior computational simplicity and efficiency to the MLE. The SWCG method performs robustly under high flows; however, poorly under low to moderate flows. Further research is recommended using field traffic data, under a variety of minor stream and major stream flow conditions for a variety of minor stream movement types, to compare critical gap estimates using MLE against MCG. Should the MCG method prove as robust as MLE, serious consideration should be given to its adoption to estimate critical gap parameters in guidelines.

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Globalisation and the emergence of knowledge-based economies have forced many countries to reform their education system. The enhancement of human capital to meet modern day demands of a knowledge economy, and equip the new generation with the capacity to meet the challenges of the 21st Century has become a priority. This change is particularly necessary in economies typical of countries, such as Kuwait, which have been dependent on the exploitation of non-renewable natural resources. Transiting from a resource-based economy to an economy based on knowledge and intellectual skills poses a key challenge for an education system. Significant in the development of this new economy has been the expansion of Information Communication Technology (ICT). In education, in particular, ICT is a tool for transforming the education setting. However, transformation is only successful where there are effective change management strategies and appropriate leadership. At the school level, rapid changes have affected the role that principals take particularly in relation to leading the change process. Therefore, this study investigated the leadership practices of school principals for embedding ICT into schools. The case study assessed two Kuwaiti secondary schools; both schools had well established ICT programs. The mode of data collection used a mixed-methods design, to address the purpose of the study, namely, to examine the leadership practices of school principals when managing the change processes associated with embedding ICT in the context of Kuwait. A theoretical model of principal leadership, developed, from the literature, documented and analysed the practices of the respective school principals. The study used the following five data sources: (a) face to face interviews (with each school principal), and two focus group interviews (with five teachers and five students, from each school); (b) school documents (related to the implementation and embedding of ICT); (c) one survey (of all teachers in each school); (d) an open-ended questionnaire (of participating principals and teachers); and (e) the observation of ICT activities (PD ICT activities and instruction meetings). The study revealed a range of strategies used by the principals and aligned with the theoretical perspective. However, these strategies needed to be refined and selectively used to fit the Kuwait context, both culturally and organisationally. The principals of Schools A and B employed three key strategies to maximise the impact on the teaching staff incorporating ICT into their teaching and learning practices. These strategies were: (a) encouragement for teaching staff to implement ICT in their teaching; (b) support to meet the material and human needs of teaching staff using ICT; and (c) provision of instructions and guidance for teaching staff in how and why such behaviours and practices should be performed. The strategies provided the basic leadership practices required to construct a successful ICT embedded implementation process. Hence, a revised model of leadership that has applicability in the adoption of ICT in Kuwait was developed. The findings provide a better understanding of how a school principal’s leadership practices impact upon the ICT embedding process. Hence, the outcome of this study informs emerging countries, which are also undergoing major change related to ICT, for example, other members of the Cooperation Council for the Arab States of the Gulf. From an educational perspective, this knowledge has the potential to support ICT-based learning environments that will help educational practitioners to effectively integrate ICT into teaching and learning that will facilitate students’ ICT engagement, and prepare them for the ICT development challenges that are associated with the new economy; this is achieved by increasing students’ knowledge and performance. Further, the study offers practical strategies that have been shown to work for school principals leading ICT implementation in Kuwait. These strategies include how to deal with the shortage in schools’ budgets, and the promotion of the ICT vision, as well as developing approaches to build collaborative culture in the schools.

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"Whe' yu' from?" The question was put to me as I wandered, camera in hand, in the old square of Spanish Town, Jamaica's former capital. The local man, lounging in the shade of one of the colonial Georgian buildings that enclose the square, was mildly curious about what he took to be a typical white tourish photgraphing the sights of the decayed historic town. At that time, my home was in Kingston where i lived with my wife and baby son. I was then working in the Jamaican Government Town Planning Department in a job that took me all over the island. Turning to my questioner, I replied, "Kingston". There was a brief pause, and then the man spoke again: "No Man! Whe' yu' really from?" I still have difficulties when asked this question. Where am I from? What does this question mean? Does it refer to where I was born, where I spent my previous life or where I live now? Does it have a broader meaning, an enquiry about my origins in terms of background and previous experience? The following chapters are my attempt to answer these questions for my own satisfaction and, I hope, for the amusement of others who may be interested in the life of an ordinary English boy whose dream to travel and see the world was realized in ways he could not possibly have imagined. Finding an appropriate title for this book was difficult. Thursday's Child, North and South and War and Peace all came to mind but, unfortunately for me, those titles had been appropriated by other writers. Thursdays's Child is quite a popular book title, presumably because people who were born on that day and, in the words of the nursery rhyme, had 'far to go', are especially likely to have travellers' tales to tell or life stories of the rags-to-riches variety. Born on a Thursday, I have travelled a lot and I suppose that I have gone far in life. Coming from a working class family, I 'got on' by 'getting a good education' and a 'good job'. I decided against adding to the list of Thursday's Children. North and South would have reflected my life in Britain, spent in both the North and South of England, and my later years, divided between the Northern and Southern Hemispheres of the globe, as well as in countries commonly referred to as the 'advanced' North and the 'underdeveloped' South. North and South has already been appropriated by Mrs Gaskell, something that did not deter one popular American writer from using the title for a book of his. My memories of World War Two and the years afterwards made War and Peace a possible candidate, but readers expectnig an epic tale of Tolstoyan proportions may have been disappointed. To my knowledge, no other book has the title "Whe' Yu' From?". I am grateful to the Jamaican man whose question lingered in my memory and provided the title of this memoir, written decades later. This book is a word picture. It is, in a sense, a self-portrait, and like all portraits, it captures something of the character, it attempts to tell the truth, but it is not the whole truth. This is because it is not my intention to write my entire life story; rather I wish to tell about some of the things in my experience of life that have seemed important or interesting to me. Unlike a painted portrait, the picture I have created is intended to suggest the passage of time. While, for most of us in Western society, time is linear and unidirectional, like the flight of an arrov or the trajectory of a bullet, memory rearranges things, calling up images of the past in no particular order, making connections that may link events in various patterns, circular, web-like, superimposed. The stream of consciousness is very unlike that of streams we encounter in the physical world. Connections are made in all directions; thoughts hop back and forth in time and space, from topic to topic. My book is a composition drawn from periods, events and thoughts as I remember them. Like life itself, it is made up of patches, some good, some bad, but in my experience, always fascinating. In recording my memories, I have been as accurate as possible. Little of what I have written is about spectacular sights and strange customs. Much of it focuses on my more modest explorations includng observations of everyday things that have attracted my attention. Reading through the chapters, I am struck by my childhood freedom to roam and engage in 'dangerous' activities like climbing trees and playing beside streams, things that many children today are no longer allowed to enjoy. Also noticeable is the survival of traditions and superstitions from the distant past. Obvious too, is my preoccupation with place names, both official ones that appear on maps and sign boards and those used by locals and children, names rarely seen in print. If there is any uniting theme to be found in what I have written, it must be my education in the fields, woods and streets of my English homeland, in the various other countries in which I have lived and travelled, as well as more formally from books and in classrooms. Much of my book is concerned with people and places. Many of the people I mention are among those who have been, and often have remained, important and close to me. Others I remember from only the briefest of encounters, but they remain in my memory because of some specific incident or circumstance that fixed a lasting image in my mind. Some of my closest friends and relatives, however, appear nowhere in these pages or they receive only the slightest mention. This is not because they played an unimportant roles in my life. It is because this book is not the whole story. Among those whe receive little or no mention are some who are especially close to me, with whom I have shared happy and sad times and who have shown me and my family much kindness, giving support when this was needed. Some I have known since childhood and have popped up at various times in my life, often in different parts of the world. Although years may pass without me seeing them, in an important sense they are always with me. These people know who they are. I hope that they know how much I love and appreciate them. When writing my memoir, I consulted a few of the people mentioned in this book, but in the main, I have relied on my own memory, asided by daiary and notebook entries and old correspondence. In the preparation of this manuscript, I benefited greatly from the expert advice and encouragement of Neil Marr of BeWrite Books. My wife Anne, inspiration for this book, also contributed in the valuable role of critic. She has my undying gratitude.

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Background: Foot ulcers are a frequent reason for diabetes-related hospitalisation. Clinical training is known to have a beneficial impact on foot ulcer outcomes. Clinical training using simulation techniques has rarely been used in the management of diabetes-related foot complications or chronic wounds. Simulation can be defined as a device or environment that attempts to replicate the real world. The few non-web-based foot-related simulation courses have focused solely on training for a single skill or “part task” (for example, practicing ingrown toenail procedures on models). This pilot study aimed to primarily investigate the effect of a training program using multiple methods of simulation on participants’ clinical confidence in the management of foot ulcers. Methods: Sixteen podiatrists participated in a two-day Foot Ulcer Simulation Training (FUST) course. The course included pre-requisite web-based learning modules, practicing individual foot ulcer management part tasks (for example, debriding a model foot ulcer), and participating in replicated clinical consultation scenarios (for example, treating a standardised patient (actor) with a model foot ulcer). The primary outcome measure of the course was participants’ pre- and post completion of confidence surveys, using a five-point Likert scale (1 = Unacceptable-5 = Proficient). Participants’ knowledge, satisfaction and their perception of the relevance and fidelity (realism) of a range of course elements were also investigated. Parametric statistics were used to analyse the data. Pearson’s r was used for correlation, ANOVA for testing the differences between groups, and a paired-sample t-test to determine the significance between pre- and post-workshop scores. A minimum significance level of p < 0.05 was used. Results: An overall 42% improvement in clinical confidence was observed following completion of FUST (mean scores 3.10 compared to 4.40, p < 0.05). The lack of an overall significant change in knowledge scores reflected the participant populations’ high baseline knowledge and pre-requisite completion of web-based modules. Satisfaction, relevance and fidelity of all course elements were rated highly. Conclusions: This pilot study suggests simulation training programs can improve participants’ clinical confidence in the management of foot ulcers. The approach has the potential to enhance clinical training in diabetes-related foot complications and chronic wounds in general.

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Young drivers are overrepresented in motor vehicle crash rates, and their risk increases when carrying similar aged passengers. Graduated Driver Licensing strategies have demonstrated effectiveness in reducing fatalities among young drivers, however complementary approaches may further reduce crash rates. Previous studies conducted by the researchers have shown that there is considerable potential for a passenger focus in youth road safety interventions, particularly involving the encouragement of young passengers to intervene in their peers’ risky driving (Buckley, Chapman, Sheehan & Davidson, 2012). Additionally, this research has shown that technology-based applications may be a promising means of delivering passenger safety messages, particularly as young people are increasingly accessing web-based and mobile technologies. This research describes the participatory design process undertaken to develop a web-based road safety program, and involves feasibility testing of storyboards for a youth passenger safety application. Storyboards and framework web-based materials were initially developed for a passenger safety program, using the results of previous studies involving online and school-based surveys with young people. Focus groups were then conducted with 8 school staff and 30 senior school students at one public high school in the Australian Capital Territory. Young people were asked about the situations in which passengers may feel unsafe and potential strategies for intervening in their peers’ risky driving. Students were also shown the storyboards and framework web-based material and were asked to comment on design and content issues. Teachers were also shown the material and asked about their perceptions of program design and feasibility. The focus group data will be used as part of the participatory design process, in further developing the passenger safety program. This research describes an evidence-based approach to the development of a web-based application for youth passenger safety. The findings of this research and resulting technology will have important implications for the road safety education of senior high school students.

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The school environment plays an important role in shaping adolescent outcomes, and research increasingly demonstrates the need to target the school social context in health promotion programs. This paper describes the research process undertaken to design a school connectedness component of an injury prevention program for early adolescents, Skills for Preventing Injury in Youth (SPIY). The connectedness component takes the form of a professional development workshop for teachers on increasing students’ connectedness to school, and this paper describes the research process used to construct program material. It also describes the methods used to encourage teachers’ implementation of connectedness strategies following program delivery. A multi-stage process of data collection included, (i) surveys with 540 Grade 9 students to examine links between school connectedness and risk-related injury, (ii) a systematic literature review of previously-evaluated school connectedness programs to determine key strategies that encourage implementation fidelity and program effectiveness, and (iii) interviews with 14 high school teachers to understand current use of connectedness strategies and ideas for program design. Findings from each stage are discussed in terms of how results informed the program design. The survey data provided information from which to frame program content, and the results of the systematic review demonstrated effective program strategies. The teacher interview data also provided program content incorporating target participants’ views and aligning with their priorities, which is important to ensure effective implementation of program strategies. A comprehensive design process provides an understanding of methods for, and may encourage, teachers’ future implementation of program strategies.

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BACKGROUND: There is evidence that children's decisions to smoke are influenced by family and friends. OBJECTIVES: To assess the effectiveness of interventions to help family members to strengthen non-smoking attitudes and promote non-smoking by children and other family members. SEARCH STRATEGY: We searched 14 electronic bibliographic databases, including the Cochrane Tobacco Addiction Group specialized register, MEDLINE, EMBASE, PsycINFO and CINAHL. We also searched unpublished material, and the reference lists of key articles. We performed both free-text Internet searches and targeted searches of appropriate websites, and we hand-searched key journals not available electronically. We also consulted authors and experts in the field. The most recent search was performed in July 2006. SELECTION CRITERIA: Randomized controlled trials (RCTs) of interventions with children (aged 5-12) or adolescents (aged 13-18) and family members to deter the use of tobacco. The primary outcome was the effect of the intervention on the smoking status of children who reported no use of tobacco at baseline. Included trials had to report outcomes measured at least six months from the start of the intervention. DATA COLLECTION AND ANALYSIS: We reviewed all potentially relevant citations and retrieved the full text to determine whether the study was an RCT and matched our inclusion criteria. Two authors independently extracted study data and assessed them for methodological quality. The studies were too limited in number and quality to undertake a formal meta-analysis, and we present a narrative synthesis. MAIN RESULTS: We identified 19 RCTs of family interventions to prevent smoking. We identified five RCTs in Category 1 (minimal risk of bias on all counts); nine in Category 2 (a risk of bias in one or more areas); and five in Category 3 (risks of bias in design and execution such that reliable conclusions cannot be drawn from the study).Considering the fourteen Category 1 and 2 studies together: (1) four of the nine that tested a family intervention against a control group had significant positive effects, but one showed significant negative effects; (2) one of the five RCTs that tested a family intervention against a school intervention had significant positive effects; (3) none of the six that compared the incremental effects of a family plus a school programme to a school programme alone had significant positive effects; (4) the one RCT that tested a family tobacco intervention against a family non-tobacco safety intervention showed no effects; and (5) the one trial that used general risk reduction interventions found the group which received the parent and teen interventions had less smoking than the one that received only the teen intervention (there was no tobacco intervention but tobacco outcomes were measured). For the included trials the amount of implementer training and the fidelity of implementation are related to positive outcomes, but the number of sessions is not. AUTHORS' CONCLUSIONS: Some well-executed RCTs show family interventions may prevent adolescent smoking, but RCTs which were less well executed had mostly neutral or negative results. There is thus a need for well-designed and executed RCTs in this area.

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Background: Enabling women to make informed decisions is a crucial component of consumer-focused maternity care. Current evidence suggests that health care practitioners’ communication of care options may not facilitate patient involvement in decision-making. The aim of this study was to investigate the effect of specific variations in health caregiver communication on women’s preferences for induction of labor for prolonged pregnancy. Methods: A convenience sample of 595 female participants read a hypothetical scenario in which an obstetrician discusses induction of labor with a pregnant woman. Information provided on induction and the degree of encouragement for the woman’s involvement in decision-making was manipulated to create four experimental conditions. Participants indicated preference with respect to induction, their perceptions of the quality of information received, and other potential moderating factors. Results: Participants who received information that was directive in favor of medical intervention were significantly more likely to prefer induction than those given nondirective information. No effect of level of involvement in decision-making was found. Participants’ general trust in doctors moderated the relationship between health caregiver communication and preferences for induction, such that the influence of information provided on preferences for induction differed across levels of involvement in decision-making for women with a low trust in doctors, but not for those with high trust. Many women were not aware of the level of information required to make an informed decision. Conclusions: Our findings highlight the potential value of strategies such as patient decision aids and health care professional education to improve the quality of information available to women and their capacity for informed decision-making during pregnancy and birth. (BIRTH 39:3 September 2012)

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Kuwait is an oil rich country planning for a future that is not dependent on exploiting natural resources. A major policy initiative has been the introduction of Information Communication and Technology (ICT) to schools. However, contextual issues and teacher capabilities in the use of ICT have limited the success of this initiative. The study examines the leadership strategies of two secondary school principals whose schools have achieved this goal. The case study draws on intensive data collected through interviews of the principals, and teachers supported by document analysis and observations. Analysis was guided by theoretical perspectives drawn from the literature which identified a range of strategies used by the principals to manage change. The principals of Schools A and B employed three key strategies to maximise the impact on the teaching staff incorporating ICT into their teaching and learning practices. These strategies were: (a) encouragement for teaching staff to implement ICT in their teaching; (b) support to meet the material and human needs of teaching staff using ICT; and (c) provision of instructions and guidance for teaching staff in how and why such behaviours and practices should be performed. The outcome of this study proposes an innovative change leadership model that informs emerging countries, which are also undergoing major change related to ICT. However, the study also revealed limitations in the implementation of ICT in the classroom and provides insights into further strategies that principals need to adopt.

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Purpose: The purpose of the study was to examine relationships between socio-demographic variables, job satisfaction and nurses’ caring experiences in a registered nurse population, as measured by the caring efficacy scale (CES) which was developed from Bandura’s social cognitive theory and Watson’s transpersonal caring theory. Methods: A cross-sectional survey was undertaken of nurses representing a variety of nursing specialties. A stratified random sample of registered nurses, who were members of a professional nursing organisation, was invited to participate in this study. Descriptive analyses, correlation analyses, one- way ANOVA tests, simple linear regression and multivariable analyses were conducted to examine if any relationships existed between these variables. Results: There were a total of 639 respondents to the national survey. The respondents (100%) showed positive perceived CES scores and 80.8% showed positive job satisfaction scores. Correlation analysis found age, years experience as a registered nurse and years in current job, all positively correlated with each other, (r >0.40: p < 0.001). CES scores were found to be positively correlated with age, years of experience as a registered nurse (r>0.1: p < 0.001) and job satisfaction (r>0.1: p < 0.001). An ANOVA found significant positive relationships between CES scores and age (p=0.05). Conclusion: Results from this study have identified that relationships between age, years of experience, job satisfaction and the perceived caring experiences of nurses’ exist. Organisational leaders may develop strategies for professional development and orientation programmes that enhance the caring experiences of nurses to provide quality patient care. The development of programmes that provide role modelling, emotional support or use verbal persuasion are needed where encouragement is required for nurses to master new skills. This may also improve job satisfaction and retention of nurses in the workplace in the current economically focussed healthcare system.

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Crowds of noncombatants play a large and increasingly recognized role in modern military operations and often create substantial difficulties for the combatant forces involved. However, realistic models of crowds are essentially absent from current military simulations. To address this problem, the authors are developing a crowd simulation capable of generating crowds of noncombatant civilians that exhibit a variety of realistic individual and group behaviors at differing levels of fidelity. The crowd simulation is interoperable with existing military simulations using a standard, distributed simulation architecture. Commercial game technology is used in the crowd simulation to model both urban terrain and the physical behaviors of the human characters that make up the crowd. The objective of this article is to present the design and development process of a simulation that integrates commercially available game technology with current military simulations to generate realistic and believable crowd behavior.

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Crowds of non-combatants play a large and increasingly recognized role in modern military operations, and often create substantial difficulties for the combatant forces involved. However, realistic models of crowds are essentially absent from current military simulations. To address this problem we are developing a crowd simulation capable of generating crowds of non-combatant civilians that exhibit a variety of realistic individual and group behaviours at differing levels of fidelity. The crowd simulation is interoperable with existing military simulations using a standard distributed simulation architecture. Commercial game technology is utilized in the crowd simulation to model both urban terrain and the physical behaviours of the human characters that make up the crowd. The objective of this paper is to present the process involved with the design and development of a simulation that integrates commercially available game technology with current military simulations in order to generate realistic and believable crowd behaviour.

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Simulation has been widely used to estimate the benefits of Cooperative Systems (CS) based on Inter-Vehicular Communications (IVC). This paper presents a new architecture built with the SiVIC simulator and the RTMaps™ multisensors prototyping platform. We introduce several improvements from a previous similar architecture, regarding IVC modelisation and vehicles’ control. It has been tuned with on-road measurements to improve fidelity. We discuss the results of a freeway emergency braking scenario (EEBL) implemented to validate our architecture’s capabilities.

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Effective digital human model (DHM) simulation of automotive driver packaging ergonomics, safety and comfort depends on accurate modelling of occupant posture, which is strongly related to the mechanical interaction between human body soft tissue and flexible seat components. This paper presents a finite-element study simulating the deflection of seat cushion foam and supportive seat structures, as well as human buttock and thigh soft tissue when seated. The three-dimensional data used for modelling thigh and buttock geometry were taken on one 95th percentile male subject, representing the bivariate percentiles of the combined hip breadth (seated) and buttock-to-knee length distributions of a selected Australian and US population. A thigh-buttock surface shell based on this data was generated for the analytic model. A 6mm neoprene layer was offset from the shell to account for the compression of body tissue expected through sitting in a seat. The thigh-buttock model is therefore made of two layers, covering thin to moderate thigh and buttock proportions, but not more fleshy sizes. To replicate the effects of skin and fat, the neoprene rubber layer was modelled as a hyperelastic material with viscoelastic behaviour in a Neo-Hookean material model. Finite element (FE) analysis was performed in ANSYS V13 WB (Canonsburg, USA). It is hypothesized that the presented FE simulation delivers a valid result, compared to a standard SAE physical test and the real phenomenon of human-seat indentation. The analytical model is based on the CAD assembly of a Ford Territory seat. The optimized seat frame, suspension and foam pad CAD data were transformed and meshed into FE models and indented by the two layer, soft surface human FE model. Converging results with the least computational effort were achieved for a bonded connection between cushion and seat base as well as cushion and suspension, no separation between neoprene and indenter shell and a frictional connection between cushion pad and neoprene. The result is compared to a previous simulation of an indentation with a hard shell human finite-element model of equal geometry, and to the physical indentation result, which is approached with very high fidelity. We conclude that (a) SAE composite buttock form indentation of a suspended seat cushion can be validly simulated in a FE model of merely similar geometry, but using a two-layer hard/soft structure. (b) Human-seat indentation of a suspended seat cushion can be validly simulated with a simplified human buttock-thigh model for a selected anthropomorphism.

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Contemporary 3D radiotherapy treatment planning relies upon the use of 3D electron density maps derived from computed tomography (CT) scans of patient anatomy, to evaluate the effects of that anatomy on radiation dose distributions. Production of these electron density maps requires that the CT numbers (Hounsfield units) that quantify the attenuation of the x-ray beam by the patient’s anatomy must be reliably converted into electron densities, using a stable calibration relationship. This study investigates the fidelity of electron density assignment in the presence of metallic prostheses and implants.