Exploring the use of a web-based virtual patient to support learning through reflection

This thesis explores the support of learning through reflection, in the context of medical students and practitioners, working through a series of simulated consultations involving the diagnosis and management of chronic illness. A model of the medical consultative process was defined, on which a web-based patient simulation was developed. This simulation can be accessed over the Internet using commonly available web-browsers. It enables users to interact with a virtual patient by taking a history, examining the patient, requesting and reviewing investigations, and choosing appropriate management strategies. The virtual patient can be reviewed over a number of consultations, and the patient outcome is dependant on the management strategy selected by the user. A second model was also developed, that adds a layer of reflection over the consultative process. While interacting with the virtual patient users are asked to formulate and test their hypotheses. Simple tools are included to encourage users to record their observations and thoughts for further learning, as well as providing links to web-based library resources. At the end of each consultation, users are asked to review their actions and indicate whether they think their actions were critical, relevant, or not relevant to the diagnosis and management of the patient in light of their current knowledge. Users also have the opportunity to compare their activity to their peers or an expert in the case under study. Three formal cycles of evaluation were undertaken during the design and development of the software. A number of clinicians were involved in the initial design to ensure there was an appropriate structure that matched clinical practice. Formative evaluation was conducted to review the usability of the application, and based on user feedback a number of changes were made to the user interface and structure of the application. A third, end user, evaluation was undertaken using a single case concerning the diagnosis and management of hypertriglyceridaemia in the context of Type 1B Glycogen Storage Disease. This evaluation involved ten medical students, five general practitioners and two specialists. The evaluation involved observation using a simplified think-aloud, as well as administration of a questionnaire. Users were engaged by the simulation, and were able to use the application with only a short period of training. Usability issues still exist with respect to the processing of natural language input, especially when asking questions of the virtual patient. Until such time that natural language recognition is able to provide satisfactory performance, alternative, list-based, methods of interaction will be required. Evaluation involving medical students, general practitioners, and specialist medical practitioners demonstrated that reflection can be supported and encouraged by providing appropriate tools, as well as by judiciously interrupting the consultative process and providing time for reflection to take place. Reflection could have been further enhanced if users had been educated on reflection as a learning modality prior to using SIMPRAC. Further work is also required to improve the simulation environment, improve the interfaces for supporting reflection, and further define the benefits of using this approach for medical education and professional development with respect to learning outcomes and behavioural change

The Optical-infrared Extinction Curve and Its Variation in the Milky Way

The dust extinction curve is a critical component of many observational programs and an important diagnostic of the physics of the interstellar medium. Here we present new measurements of the dust extinction curve and its variation toward tens of thousands of stars, a hundred-fold larger sample than in existing detailed studies. We use data from the APOGEE spectroscopic survey in combination with ten-band photometry from Pan-STARRS1, the Two Micron All-Sky Survey, and Wide-field Infrared Survey Explorer. We find that the extinction curve in the optical through infrared is well characterized by a one-parameter family of curves described by R(V). The extinction curve is more uniform than suggested in past works, with $\sigma (R(V))=0.18$, and with less than one percent of sight lines having $R(V)\gt 4$. Our data and analysis have revealed two new aspects of Galactic extinction: first, we find significant, wide-area variations in R(V) throughout the Galactic plane. These variations are on scales much larger than individual molecular clouds, indicating that R(V) variations must trace much more than just grain growth in dense molecular environments. Indeed, we find no correlation between R(V) and dust column density up to $E(B-V)\approx 2$. Second, we discover a strong relationship between R(V) and the far-infrared dust emissivity

The association between outcome-based quality indicators for intensive care units

Intensive Car

The use of a registry database in clinical trial design: assessing the influence of entry criteria on statistical power and number of eligible patients.

Item does not contain fulltextRandomized clinical trials (RCTs) are prospective empirical studies used to investigate the effect of a particular medical intervention. The design of a clinical trial is a delicate decision process, as each of the decisions that are taken in this process influences the eventual result of the clinical trial. Despite the efforts that are put into trial design, many trials fail to show an effect of the intervention. In some of these situations the intervention may be truly ineffective, however, more often this is caused by problems with the inclusion of patients and a resulting lack of statistical power to show the effect. To avoid this problem, in the design of a trial, the statistical power that can be achieved with the current design choices is calculated and balanced with economic considerations. In the choice of the entry criteria however, an important step in the design process, the influence of the chosen criteria on statistical power and number of eligible patients is not quantified. As these criteria influence the characteristics of the study population and the number of patients that will be eligible for the trial, and thereby the chances of finding an effect of the intervention, we believe that also in the choice of entry criteria explicit estimates of the number of eligible patients should be made. This paper presents a method to arrive at precise, objective estimates of statistical power and the number of eligible patients, using a registry database. Furthermore, we describe how this method is incorporated in the process of choosing entry criteria for a clinical trial. We illustrate the method with an example in the area of severe sepsis

A multifaceted feedback strategy alone does not improve the adherence to organizational guideline-based standards: a cluster randomized trial in intensive care

Contains fulltext : 155179.pdf (publisher's version ) (Open Access)BACKGROUND: Organizational data such as bed occupancy rate and nurse-to-patient ratio are related to clinical outcomes and to the efficient use of intensive care unit (ICU) resources. Standards for these performance indicators are provided in guidelines. We studied the effects of a multifaceted feedback strategy to improve the adherence to these standards. METHODS: In a cluster randomized controlled study design the intervention ICUs received extensive monthly feedback reports, they received outreach visits and initiated a quality improvement team. The control ICUs received limited quarterly feedback reports only. We collected primary data prospectively within the setting of a Dutch national ICU registry over a 14-month study period. The target indicators were bed occupancy rate (aiming at 80 % or below) and nurse-to-patient ratio (aiming at 0.5 or higher). Data were collected per 8-h nursing shift. Logistic regression analysis was performed. For both study end points, the odds ratios (OR) for improvements at follow-up versus at baseline were calculated separately for control and intervention ICUs. RESULTS: We analyzed data on 67,237 nursing shifts. The bed occupancy rate did not improve in the intervention group compared to baseline (adjusted OR 0.88; 95 % confidence interval (CI), 0.62-1.27) or compared to control group (OR 0.67; 95 % CI 0.39-1.15). The nurse-to-patient ratio did not improve (OR 0.72; 95 % CI 0.41-1.26 compared to baseline and OR 0.65; 95 % CI 0.35-1.19 compared to control group). CONCLUSIONS: A multifaceted feedback intervention did not improve the adherence to guideline-based standards on the organizational issues bed occupancy rate and nurse-to-patient ratio in the ICU. The reasons may be a limited confidence in data quality, the lack of practical tools for improvement, and the relatively short follow-up. TRIAL REGISTRATION: ISRCTN: ISRCTN50542146

Using hierarchical dynamic Bayesian networks to investigate dynamics of organ failure in patients in the Intensive Care Unit

Perioperative Medicine: Efficacy, Safety and Outcom

What is needed to implement a web-based audit and feedback intervention with outreach visits to improve care quality:A concept mapping study among cardiac rehabilitation teams

INTRODUCTION: Evidence on successful quality improvement (QI) in health care requires quantitative information from randomized clinical trials (RCTs) on the effectiveness of QI interventions, but also qualitative information from professionals to understand factors influencing QI implementation. OBJECTIVE: Using a structured qualitative approach, concept mapping, this study determines factors identified by cardiac rehabilitation (CR) teams on what is needed to successfully implement a web-based audit and feedback (A&F) intervention with outreach visits to improve the quality of CR care. METHODS: Participants included 49 CR professionals from 18 Dutch CR centres who had worked with the A&F system during a RCT. In three focus group sessions participants formulated statements on factors needed to implement QI successfully. Subsequently, participants rated all statements for importance and feasibility and grouped them thematically. Multi dimensional scaling was used to produce a final concept map. RESULTS: Forty-two unique statements were formulated and grouped into five thematic clusters in the concept map. The cluster with the highest importance was QI team commitment, followed by organisational readiness, presence of an adequate A&F system, access to an external quality assessor, and future use and functionalities of the A&F system. CONCLUSION: Concept mapping appeared efficient and useful to understand contextual factors influencing QI implementation as perceived by healthcare teams. While presence of a web-based A&F system and external quality assessor were seen as instrumental for gaining insight into performance and formulating QI actions, QI team commitment and organisational readiness were perceived as essential to actually implement and carry out these actions. These two sociotechnical factors should be taken into account when implementing and evaluating the success of QI implementations in future research