An integer programming Model for the Hospitals/Residents Problem with Couples

The Hospitals/Residents problem with Couples (hrc) is a generalisation of the classical Hospitals/Residents problem (hr) that is important in practical applications because it models the case where couples submit joint preference lists over pairs of (typically geographically close) hospitals. In this paper we give a new NP-completeness result for the problem of deciding whether a stable matching exists, in highly restricted instances of hrc. Further, we present an Integer Programming (IP) model for hrc and extend it the case where preference lists can include ties. Further, we describe an empirical study of an IP model for HRC and its extension to the case where preference lists can include ties. This model was applied to randomly generated instances and also real-world instances arising from previous matching runs of the Scottish Foundation Allocation Scheme, used to allocate junior doctors to hospitals in Scotland

Prolonging life and delaying death: The role of physicians in the context of limited intensive care resources

Critical care is in an emerging crisis of conflict between what individuals expect and the economic burden society and government are prepared to provide. The goal of critical care support is to prevent suffering and premature death by intensive therapy of reversible illnesses within a reasonable timeframe. Recently, it has become apparent that early support in an intensive care environment can improve patient outcomes. However, life support technology has advanced, allowing physicians to prolong life (and postpone death) in circumstances that were not possible in the recent past. This has been recognized by not only the medical community, but also by society at large. One corollary may be that expectations for recovery from critical illness have also become extremely high. In addition, greater numbers of patients are dying in intensive care units after having receiving prolonged durations of life-sustaining therapy. Herein lies the emerging crisis – critical care therapy must be available in a timely fashion for those who require it urgently, yet its provision is largely dependent on a finite availability of both capital and human resources. Physicians are often placed in a troubling conflict of interest by pressures to use health resources prudently while also promoting the equitable and timely access to critical care therapy. In this commentary, these issues are broadly discussed from the perspective of the individual clinician as well as that of society as a whole. The intent is to generate dialogue on the dynamic between individual clinicians navigating the complexities of how and when to use critical care support in the context of end-of-life issues, the increasing demands placed on finite critical care capacity, and the reasonable expectations of society

A Survey of IS/IT Investment Evaluation Practices in Australia: Some Preliminary Results

In modern organizations a large portion of senior management's time is now being spent on finding ways to measure the contribution of their organizations IS/IT investments to business performance. It has been shown that IS/IT investments in many organizations are huge and increasing rapidly every year and yet there is still a lack of understanding of the impact of the proper IS/IT investment evaluation processes and practices in these organizations. At the same time, the issue of expected and actual benefits realized from IS/IT investments has also generated a significant amount of debate in the IS/IT literature amongst researchers and practitioners, though most of the published research comes from the USA and UK. This study has addressed that issue through a survey of the CIOs of Australia's largest 500 organisations. The results indicate that a variety of formal IS/IT investment evaluation processes and techniques are used, costs and budgets are of great concern, there is a strong emphasis on cost reduction and other benefits, and a reasonable level of confidence in the delivery of these benefits. Most organizations used a formal methodology or process for IS/IT investment evaluation, and financially based evaluation techniques such as NPV and ROI which, though not perfect, often do try to incorporate intangible benefits into the process. These and other results are presented in the paper, and suggestions for further work included

Using Ontological Ideas to Facilitate the Comparison of Requirements Elicitation Methods

There are a plethora of system development methods available to practitioners, all purporting to be the best method. This variety brings with it an element of choice which can be perceived as a problem in itself, quite apart from the issue of developing a system. This paper uses elements of the ontological framework of Bunge, Wand and Weber to critically examine the constructs of several methods used to develop requirements specifications (and, in particular, business process models), notably the Business Rules Diagram (BRD) Method and the Unified Modelling Language (UML)

Popular matchings with two-sided preferences and one-sided ties

We are given a bipartite graph $G = (A \cup B, E)$ where each vertex has a preference list ranking its neighbors: in particular, every $a \in A$ ranks its neighbors in a strict order of preference, whereas the preference lists of $b \in B$ may contain ties. A matching $M$ is popular if there is no matching $M'$ such that the number of vertices that prefer $M'$ to $M$ exceeds the number of vertices that prefer $M$ to~$M'$. We show that the problem of deciding whether $G$ admits a popular matching or not is NP-hard. This is the case even when every $b \in B$ either has a strict preference list or puts all its neighbors into a single tie. In contrast, we show that the problem becomes polynomially solvable in the case when each $b \in B$ puts all its neighbors into a single tie. That is, all neighbors of $b$ are tied in $b$'s list and $b$ desires to be matched to any of them. Our main result is an $O(n^2)$ algorithm (where $n = |A \cup B|$) for the popular matching problem in this model. Note that this model is quite different from the model where vertices in $B$ have no preferences and do not care whether they are matched or not.Comment: A shortened version of this paper has appeared at ICALP 201

Challenges in Improving Information Security Practice in Australian General

The status of information security in Australian medical general practice is discussed together with a review of the challenges facing small practices that often lack the technical knowledge and skill to secure patient information by themselves. It is proposed that an information security governance framework is required to assist practices in identifying weaknesses and gaps and then to plan and implement how to overcome their shortcomings through policies, training and changes to processes and management structure

Frailty in the critically ill: a novel concept

The concept of frailty has been defined as a multidimensional syndrome characterized by the loss of physical and cognitive reserve that predisposes to the accumulation of deficits and increased vulnerability to adverse events. Frailty is strongly correlated with age, and overlaps with and extends aspects of a patient's disability status (that is, functional limitation) and/or burden of comorbid disease. The frail phenotype has more specifically been characterized by adverse changes to a patient's mobility, muscle mass, nutritional status, strength and endurance. We contend that, in selected circumstances, the critically ill patient may be analogous to the frail geriatric patient. The prevalence of frailty amongst critically ill patients is currently unknown; however, it is probably increasing, based on data showing that the utilization of intensive care unit (ICU) resources by older people is rising. Owing to the theoretical similarities in frailty between geriatric and critically ill patients, this concept may have clinical relevance and may be predictive of outcomes, along with showing important interaction with several factors including illness severity, comorbid disease, and the social and structural environment. We believe studies of frailty in critically ill patients are needed to evaluate how it correlates with outcomes such as survival and quality of life, and how it relates to resource utilization, such as length of mechanical ventilation, ICU stay and duration of hospitalization. We hypothesize that the objective measurement of frailty may provide additional support and reinforcement to clinicians confronted with end-of-life decisions on the appropriateness of ICU support and/or withholding of life-sustaining therapies

An Information Security Governance Framework for Australian Primary Care Health Providers

The competitive nature of business and society means that the protection of information, and governance of the information security function, is increasingly important. This paper introduces the notion of a governance framework for information security for health providers. It refines the idea of an IT Balanced Scorecard into a scorecard process for use in governing information security for primary care health providers, where IT and security skills may be limited. The approach amends and justifies the four main elements of the scorecard process. The existence of a governance framework specifically tailored for the needs of primary care practice is a critical success factor if such organizations are to move to a robust level of information security. The challenge is twofold. Firstly, measures for governance need to be understandable to the target audience using the framework. Secondly, the number of measures needs to be controllable otherwise the process will become unviable and unused. This research synthesizes existing models and industry standards to formulate a new governance process that meets these two important criteria. The contribution of this research is in the refinement of governance metrics to make them useful to healthcare providers, specifically in relation to IT and new information communication technologies

Early post-immobilization pain at rest, movement evoked pain, and their ratio as potential predictors of pain and disability at six- and 12-months after distal radius fracture

Background: Removal of immobilization is a critical phase of distal radius fracture (DRF) rehabilitation, typically occurring by 2 months post injury. This study examined the extent to which pain at rest (PAR), movement evoked pain (MEP), or the ratio between those (MEPR) assessed at 2-months after DRF predicts the occurrence of chronic pain or disability at 6- and 12-months after the injury. Methods: This secondary analysis of a prospective cohort study was done at the Hand and Upper Limb Centre (HULC), London, Ontario, Canada. A total of 229 patients with DRF (159 (69.4%) women) were included. Scores for the pain and function subscales of the Patient-Rated Wrist Evaluation (PRWE) were extracted for 2, 6 and 12 months after DRF. Logistic as well as nonlinear quartile regression examined whether PAR and MEP predicted the severity of chronic pain and disability at 6- and 12-months after DRF. Receiver Operating Characteristics Curve were plotted, where area under the curve (AUC) examined the accuracy of the PAR and MEP scores in classifying those who experienced chronic pain and disability. Results: Scores of ≥3 (AUC of 0.77) for PAR or ≥ 6 (AUC of 0.78) for MEP at 2 months after DRF predicted moderate to severe wrist pain at 6-months, whereas scores of ≥7 (AUC of 0.79) for MEP at 2-months predicted ongoing wrist disability at 6-months after the injury. The MEPR of 2 ≤ or ≥ 8 at 2-months was associated with adverse pain at 6-months and functional outcomes at 6- and 12-months (R-square = 0.7 and 0.04 respectively), but prediction accuracy was very poor (AUC ≤ 0.50). Conclusion: Chronic wrist-related pain at 6-months can be predicted by either elevated PAR ≥ 3/10) or MEP (≥ 6/10) reported at 2-months after the injury, while disability experienced at 6-months after DRF is best predicted by MEP (≥7/10) reported at 2-months. The ratio of these two pain indicators increases assessment complexity and reduces classification accuracy