23,807 research outputs found

    Robust Appointment Scheduling with Heterogeneous Costs

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    Designing simple appointment systems that under uncertainty in service times, try to achieve both high utilization of expensive medical equipment and personnel as well as short waiting time for patients, has long been an interesting and challenging problem in health care. We consider a robust version of the appointment scheduling problem, introduced by Mittal et al. (2014), with the goal of finding simple and easy-to-use algorithms. Previous work focused on the special case where per-unit costs due to under-utilization of equipment/personnel are homogeneous i.e., costs are linear and identical. We consider the heterogeneous case and devise an LP that has a simple closed-form solution. This solution yields the first constant-factor approximation for the problem. We also find special cases beyond homogeneous costs where the LP leads to closed form optimal schedules. Our approach and results extend more generally to convex piece-wise linear costs. For the case where the order of patients is changeable, we focus on linear costs and show that the problem is strongly NP-hard when the under-utilization costs are heterogeneous. For changeable order with homogeneous under-utilization costs, it was previously shown that an EPTAS exists. We instead find an extremely simple, ratio-based ordering that is 1.0604 approximate

    Are We Insane? The Quest for Proportionality in the Discovery Rules of the Federal Rules of Civil Procedure

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    Atrial fibrillation is a common heart arrhythmia which is characterized by a missing or irregular contraction of the atria. The disease is a risk factor for other more serious diseases and the total medical costs in society are extensive. Therefore it would be beneficial to improve and optimize the prevention and detection of the disease.   Pulse palpation and heart auscultation can facilitate the detection of atrial fibrillation clinically, but the diagnosis is generally confirmed by an ECG examination. Today there are several algorithms that detect atrial fibrillation by analysing an ECG. A common method is to study the heart rate variability (HRV) and by different types of statistical calculations find episodes of atrial fibrillation which deviates from normal sinus rhythm.   Two algorithms for detection of atrial fibrillation have been evaluated in Matlab. One is based on the coefficient of variation and the other uses a logistic regression model. Training and testing of the algorithms were done with data from the Physionet MIT database. Several steps of signal processing were used to remove different types of noise and artefacts before the data could be used.   When testing the algorithms, the CV algorithm performed with a sensitivity of 91,38%, a specificity of 93,93% and accuracy of 92,92%, and the results of the logistic regression algorithm was a sensitivity of 97,23%, specificity of 93,79% and accuracy of 95,39%. The logistic regression algorithm performed better and was chosen for implementation in Java, where it achieved a sensitivity of 97,31%, specificity of 93,47% and accuracy of 95,25%.Förmaksflimmer Àr en vanlig hjÀrtrytmrubbning som kÀnnetecknas av en avsaknad eller oregelbunden kontraktion av förmaken. Sjukdomen Àr en riskfaktor för andra allvarligare sjukdomar och de totala kostnaderna för samhÀllet Àr betydande. Det skulle dÀrför vara fördelaktigt att effektivisera och förbÀttra prevention samt diagnostisering av förmaksflimmer.   Kliniskt diagnostiseras förmaksflimmer med hjÀlp av till exempel pulspalpation och auskultation av hjÀrtat, men diagnosen brukar faststÀllas med en EKG-undersökning. Det finns idag flertalet algoritmer för att detektera arytmin genom att analysera ett EKG. En av de vanligaste metoderna Àr att undersöka variabiliteten av hjÀrtrytmen (HRV) och utföra olika sorters statistiska berÀkningar som kan upptÀcka episoder av förmaksflimmer som avviker frÄn en normal sinusrytm.   I detta projekt har tvÄ metoder för att detektera förmaksflimmer utvÀrderats i Matlab, en baseras pÄ berÀkningar av variationskoefficienten och den andra anvÀnder sig av logistisk regression. EKG som kommer frÄn databasen Physionet MIT anvÀnds för att trÀna och testa modeller av algoritmerna. Innan EKG-signalen kan anvÀndas mÄste den behandlas för att ta bort olika typer av brus och artefakter.   Vid test av algoritmen med variationskoefficienten blev resultatet en sensitivitet pÄ 91,38%, en specificitet pÄ 93,93% och en noggrannhet pÄ 92,92%. För logistisk regression blev sensitiviteten 97,23%, specificiteten 93,79% och noggrannheten 95,39%. Algoritmen med logistisk regression presterade bÀttre och valdes dÀrför för att implementeras i Java, dÀr uppnÄddes en sensitivitet pÄ 91,31%, en specificitet pÄ 93,47% och en noggrannhet pÄ 95,25%

    The organizational implications of medical imaging in the context of Malaysian hospitals

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    This research investigated the implementation and use of medical imaging in the context of Malaysian hospitals. In this report medical imaging refers to PACS, RIS/HIS and imaging modalities which are linked through a computer network. The study examined how the internal context of a hospital and its external context together influenced the implementation of medical imaging, and how this in turn shaped organizational roles and relationships within the hospital itself. It further investigated how the implementation of the technology in one hospital affected its implementation in another hospital. The research used systems theory as the theoretical framework for the study. Methodologically, the study used a case-based approach and multiple methods to obtain data. The case studies included two hospital-based radiology departments in Malaysia. The outcomes of the research suggest that the implementation of medical imaging in community hospitals is shaped by the external context particularly the role played by the Ministry of Health. Furthermore, influences from both the internal and external contexts have a substantial impact on the process of implementing medical imaging and the extent of the benefits that the organization can gain. In the context of roles and social relationships, the findings revealed that the routine use of medical imaging has substantially affected radiographers’ roles, and the social relationships between non clinical personnel and clinicians. This study found no change in the relationship between radiographers and radiologists. Finally, the approaches to implementation taken in the hospitals studied were found to influence those taken by other hospitals. Overall, this study makes three important contributions. Firstly, it extends Barley’s (1986, 1990) research by explicitly demonstrating that the organization’s internal and external contexts together shape the implementation and use of technology, that the processes of implementing and using technology impact upon roles, relationships and networks and that a role-based approach alone is inadequate to examine the outcomes of deploying an advanced technology. Secondly, this study contends that scalability of technology in the context of developing countries is not necessarily linear. Finally, this study offers practical contributions that can benefit healthcare organizations in Malaysia

    Improving healthcare empowerment through breast cancer patient navigation: a mixed methods evaluation in a safety-net setting.

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    BackgroundBreast cancer mortality rates in the U.S. remain relatively high, particularly among ethnic minorities and low-income populations. Unequal access to quality care, lower follow up rates, and poor treatment adherence contribute to rising disparities among these groups. Healthcare empowerment (HCE) is theorized to improve patient outcomes through collaboration with providers and improving understanding of and compliance with treatment. Patient navigation is a health care organizational intervention that essentially improves healthcare empowerment by providing informational, emotional, and psychosocial support. Patient navigators address barriers to care through multilingual coordination of treatment and incorporation of access to community services, support, and education into the continuum of cancer care.MethodsUtilizing survey and qualitative methods, we evaluated the patient navigation program in a Northern California safety-net hospital Breast Clinic by assessing its impact on patients' experiences with cancer care and providers' perspectives on the program. We conducted qualitative interviews with 16 patients and 4 service providers, conducted approximately 66 hours of clinic observations, and received feedback through the self-administered survey from 66 patients.ResultsThe role of the patient navigator at the Breast Clinic included providing administrative assistance, psychosocial support, improved knowledge, better understanding of treatment process, and ensuring better communication between patients and providers. As such, patient navigators facilitated improved collaboration between patients and providers and understanding of interdisciplinary care processes. The survey results suggested that the majority of patients across all ethnic backgrounds and age groups were highly satisfied with the program and had a positive perception of their navigator. Interviews with patients and providers highlighted the roles of a navigator in ensuring continuity of care, improving treatment completion rates, and reducing providers' workload and waiting time. Uncertainty about the navigator's role among the patients was a weakness of the program.ConclusionsPatient navigation in the Breast Clinic had a positive impact on patients' experiences with care and healthcare empowerment. Clarifying uncertainties about the navigators' role would aid successful outcomes

    Re-engineering the outpatient process flow of a multi-speciality hospital

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    Manufacturing concepts such as Just-in-Time, Lean and Six-Sigma, Japanese 5S, Materials Requirement Planning, Scheduling and Capacity Management have been applied in the Healthcare industries in the West for the last decade and has yielded positive results. In this study, these concepts and philosophies have been applied to an Indian Multi-speciality Hospital to improve its OPD process flow and increase patient satisfaction. The Outpatients Department (OPD) is usually the most crowded sector in a hospital. The frequent problems encountered include the waiting period for consultation, an unpredictable number of Walk-in patients, insufficient and operationally deficient OPD reception staff and unattended appointment patients. This study aims at, identifying methods to standardise OPD operations management. It has made the process more efficient through optimum resource utilisation. This will increase patient satisfaction by meeting and exceeding their expectations while maintaining quality of care. This research was conducted by mapping the process flow and using the data that was collected through an observational, cross-sectional, non-interventional study. Though there were a comprehensive set of recommendations at the end of the study, only a few could be implemented due to the introduction of a new Hospital Information System (HIS) software putting the implementation plan on hold

    Discrete Event Simulations

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    Considered by many authors as a technique for modelling stochastic, dynamic and discretely evolving systems, this technique has gained widespread acceptance among the practitioners who want to represent and improve complex systems. Since DES is a technique applied in incredibly different areas, this book reflects many different points of view about DES, thus, all authors describe how it is understood and applied within their context of work, providing an extensive understanding of what DES is. It can be said that the name of the book itself reflects the plurality that these points of view represent. The book embraces a number of topics covering theory, methods and applications to a wide range of sectors and problem areas that have been categorised into five groups. As well as the previously explained variety of points of view concerning DES, there is one additional thing to remark about this book: its richness when talking about actual data or actual data based analysis. When most academic areas are lacking application cases, roughly the half part of the chapters included in this book deal with actual problems or at least are based on actual data. Thus, the editor firmly believes that this book will be interesting for both beginners and practitioners in the area of DES
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