Rid and Wendler propose the development of a Patient Preference Predictor (PPP), an actuarial model for predicting incapacitated patient’s life-sustaining treatment preferences across a wide range of end-of-life scenarios. An actuarial approach to end-of-life decision making has enormous potential, but transferring the logic of actuarial prediction to end-of-life decision making raises several conceptual complexities and logistical problems that need further consideration. Actuarial models have proven effective in targeted prediction tasks, but no evidence supports their effectiveness in the kind of broad (...) spectrum prediction task that is the proposed goal of the PPP. We argue that a more focused approach, targeting specific medical conditions and generating treatment predictions based on the preferences of individuals with actual disease experience, is both more firmly grounded in past research and is a more prudent initial strategy for exploring the efficacy of actuarial prediction in end-of-life decision making. (shrink)

A theory of the joint measurement of quantum mechanical observables is generalized in order to make it applicable to the measurement of the local observables of field theory. Subsequently, the property of local commutativity, which is usually introduced as a postulate, is derived by means of the theory of measurement from a requirement of mutual nondisturbance, which, for local observables performed at a spacelike distance from each other, is interpreted as a requirement of macrocausality. Alternative attempts at establishing a deductive (...) relationship between relativistic causality and local commutativity are reviewed, but found wanting, either because of the assumption of an unwarranted objectivity of the object system (algebraic approach) or because of the use of a projection postulate (operational approach). Finally, the quantum mechanical nonobjectivity is related to certain features of nonlocality which are present in the formalism of quantum mechanics. (shrink)

From early sage philosophers to Leopold Senghor of Senegal and Steve Biko of South Africa, African thinking has challenged the way we think. As we enter a new millenium, the perspectives provided in this volume offer wise and refreshing alternatives to problems of self and society, culture, aesthetics, metaphysics and religion. Out of Africa always something new, and in these pages contemporary problems of cross-cultural cognition and post-coloniality are not only addressed, but also enacted. The reader witnesses the collision and (...) the coalescence of cultures in the writings of philosophers from Africa. (shrink)

Doctors are regularly confronted with requests for sterilisation of mentally handicapped people who cannot give consent for themselves. They ought to act in a medical vacuum because there doesn't exist a consensus about a model for decision making on this matter. In this article a model for decision making is proposed, based on a review of the literature and our own research data. We have attempted to select and classify certain factors which could enable us to arrive at an ethically (...) justifiable method of making a medical decision. In doing so we distinguish two major criteria: heredity and parenting competence, and six minor criteria: conception risk, IQ, age, personality, medical aspects and prognosis and finally support and guidance for the mentally handicapped person. The major criteria give rise to a "situation of necessity". In this situation the physician is confronted with a conflict of values and interests. The minor criteria are of an entirely different ethical order. They can only be considered once the major criteria have created a "situation of necessity". Ultimately it comes down to deciding whether the benefits of sterilisation outweigh the drawbacks and whether the means are appropriate to the end, where efficient contraception is the end and irreversible sterilisation is the means. (shrink)

A construction is described of a cartesian closed category A with exactly two elements out of a C-monoid such that can be recovered from A without reference to the construction.

The use of the Quality Adjusted Life-Year (QALY) as a measure of the benefit obtained from health care expenditure has been attacked on the ground that it gives a lower value to preserving the lives of people with a permanent disability or illness than to preserving the lives of those who are healthy and not disabled. The reason for this is that the quality of life of those with illness or disability is ranked, on the QALY scale, below that of (...) someone without a disability or illness. Hence we can, other things being equal, gain more QALYs by saving the lives of those without a permanent disability or illness than by saving the lives of those who are disadvantaged in these ways. But to do so puts these disadvantaged people under a kind of double jeopardy. Not only do they suffer from the disability or illness, but because of it, a low priority is given to forms of health care that can preserve their lives. This, so the objection runs, is unjust or unfair. This article assesses this objection to the use of QALYs as a basis for allocating health care resources. It seeks to determine what is sound in the double jeopardy objection, and then to show that the defender of QALYs has an adequate response to it. (shrink)

Let us call an integer part of an ordered field any subring such that every element of the field lies at distance less than 1 from a unique element of the ring. We show that every real closed field has an integer part.

Harris levels two main criticisms against our original defence of QALYs (Quality Adjusted Life Years). First, he rejects the assumption implicit in the QALY approach that not all lives are of equal value. Second, he rejects our appeal to Rawls's veil of ignorance test in support of the QALY method. In the present article we defend QALYs against Harris's criticisms. We argue that some of the conclusions Harris draws from our view that resources should be allocated on the basis of (...) potential improvements in quality of life and quantity of life are erroneous, and that others lack the moral implications Harris claims for them. On the other hand, we defend our claim that a rational egoist, behind a veil of ignorance, could consistently choose to allocate life-saving resources in accordance with the QALY method, despite Harris's claim that a rational egoist would allocate randomly if there is no better than a 50% chance of being the recipient. (shrink)

For the successful achievement of evidence-based practice, clinicians, managers and purchasers need evidence on whether a particular intervention works and ways to judge the appropriateness of the outcome criteria and measures used. Guidance is needed on what outcome measure to use, especially within routine clinical care settings. Beginning with a re-clarification of the difference between a health status and an outcome measure, the paper presents an evaluative checklist for use by clinical audit and research staff to review outcome measures for (...) use in routine care settings. Central features include the user-centredness of the measure, its psychometric properties, feasibility of use and utility. The applicability of the checklist is illustrated for outcome measurement in diabetes and stroke care. A modified form of the checklist is proposed for use by the busy clinician as an aid to the critical review of research papers within the context of evidence-based practice and to aid health care practitioners' choice of which outcome measure(s) to use within routine clinical care. (shrink)

Patient centred diagnosis is best practised through shared decision making; an iterative dialogue between doctor and patient, whichrespects a patient’s needs, values, preferences, and circumstances. -/- Shared decision making for diagnostic situations differs fundamentally from that for treatment decisions. This has important implications when considering its practical application. -/- The nature of dialogue should be tailored to the specific diagnostic decision; scenarios with higher stakes or uncertainty usually require more detailed conversations.

Background: Recent research demonstrates that people sometimes make different medical decisions for others than they would make for themselves. This finding is particularly relevant to end-of-life decisions, which are often made by surrogates and require a trade-off between prolonging life and maintaining quality of life. We examine the impact of decision role, patient age, decision maker age and multiple individual differences on these treatment decisions. Methods: Participants read a scenario about a terminally ill cancer patient faced with a choice between (...) an aggressive chemotherapy regimen that will extend life by two years and palliative treatments to control discomfort for one remaining month. Participants were randomly assigned to one of three decision roles (patient, physician, or an abstract other) and the scenario randomly varied whether the patient was described as 25 or 65-years old. Results: When deciding for a 65-year old patient, approximately 60% of participants selected aggressive chemotherapy regardless of decision role. When deciding for a 25-year old patient, however, participants were more likely to select chemotherapy for a patient (physician role) or another person (abstract other) than for themselves (70%, 67%, and 59%, respectively). In addition, confidence that powerful others (eg, physicians) control one’s health, as well as respondents’ age and race, consistently predicted treatment choices. Conclusions: Patient age appears to influence medical decisions made for others but not those that we make for ourselves. These findings may help to explain the discord that often occurs when younger cancer patients refuse life-extending treatments. (shrink)

Harris argues that if QALYs are used only 50% of the population will be eligible for survival, whereas if random methods of allocation are used 100% will be eligible. We argue that this involves an equivocation in the use of "eligible", and provides no support for the random method. There is no advantage in having a 100% chance of being "eligible" for survival behind a veil of ignorance if you still only have a 50% chance of survival once the veil (...) is lifted. A 100% chance of a 50% chance is still only a 50% chance. We also argue that Harris provides no plausible way of dealing with the criticism that his random method of allocation may result in the squandering of resources. (shrink)

It is demonstrated on the basis of the Dirac equation that quarks cannot be confined by a vector gluon potential of the form(r/r 0)a or[ln(r/r 0]a, a>0, if the quark-gluon interaction conserves parity. In order to confine quarks with the parity-conserving interaction, the effective gluon potential must be a pseudovector or a scalar. These are shown in a simple Yang-Mills field with theSU(2) group.