The economics of 'more research is needed'.

BACKGROUND: Results from epidemiology and other health research affect millions of life-years and billions of dollars, and the research directly consumes millions of dollars. Yet we do little to assess the value of research projects for future policy, even amid the ubiquitous assertions that 'more research is necessary' on a given topic. This methodological proposal outlines the arguments for why and how ex ante assessments can inform us about the value of a particular piece of further research on a topic. METHODS: Economics and decision theory concepts-cost-benefit analysis and probability-weighted predictions of outcomes-allow us to calculate the payoff from applied health research based on resulting decisions. Starting with our probability distribution for the parameters of interest, a Monte Carlo simulation generates the distribution of outcomes from a particular new study. Each true value and outcome are associated with a policy decision, and improved decisions are valued to give us the study's contribution as applied research. RESULTS: The analysis demonstrates how to calculate the expected value of further research, for a simplified case, and assess whether it is really warranted. Perhaps more important, it points out what the measure of the value of a further study ought to be. CONCLUSIONS: It is quite possible to improve our technology for assessing the value of particular pieces of further research on a topic. However, this will only happen if the need and possibility are recognized by methodologists and applied researchers.

Complex systems model of dietary choice with implications for improving diets and promoting vegetarianism.

An important step toward improving nutrition and promoting vegetarianism in the general population is to understand how consumers make dietary choices. Researchers from many clinical and social sciences are interested in dietary choice but have not combined their research into a comprehensive model to explain consumer actions. No one model has offered a good explanation for the fact that, although many people successfully change their diet significantly (often toward health-improving, plant-based diets) and are happy with the change, the public and health professionals often perceive dietary change as being difficult and unlikely to succeed. I have termed these observations "the paradox of dietary change." The present computer model uses the emerging science of complex systems analysis, which offers an intuitive method for studying evidence about dietary choice from many fields, including public health, clinical science, economics, sociology, marketing, and genetics, and for combining individual choice with social interaction. The results suggest an explanation for the paradox and methods for helping society shift toward healthier and more plant-based diets. In particular, they suggest how and why major changes might be easier to make than incremental ones, and why this makes dietary change seem more difficult to consumers than it actually is.

Science and policy implications of defining environmental justice.

Although 'environmental justice' is an increasingly important issue for policy makers and researchers, it remains for many a vague and abstract notion that is hard to define in practical, real-world terms. Part of the problem is that environmental justice is a complex, multidimensional construct that cannot easily be defined. Our aim in this article is to identify fundamental dimensions of environmental justice and highlight the resulting questions that are an inherent part of putting principles into practice. We argue that to have a constructive and informed debate about this emotionally charged topic, it is necessary to have a clear and workable definition of environmental justice. We do not propose our own definition, but instead point out that there are many possible legitimate definitions depending on one's beliefs, opinions, and values. The central point is not that a particular definition is right or wrong, but rather than choosing a definition has distinct implications for the formulation, implementation, and evaluation of both policy and science. These critical choices should be made explicit so that public dialogue can focus on the substance of this important policy issue.

Central vessel trauma.

During a 24 month period, 30 patients were treated for central vessel trauma (CVT). Injured vessels included all of the major arteries and veins in the chesk, neck and abdomen except the infrarenal aorta. Overall survival was 70 per cent. Experience with specific injuries is reviewed with commentary on surgical access to difficult areas including the thoracic outlet, suprarenal aorta and inferior vena cava. Common factors in the nine deaths are reviewed with the findings that cardiac arrest at any time during pre- or intraoperative management is uniformly lethal; emergency thoracotomy for control of bleeding carries an expectedly high mortality; cross-clamping of the descending thoracic aorta to control hemoperitoneum has a limit of tolerance of about one hour, and prolonged shock, whether compensated or profound is poorly tolerated and is associated with a high mortality.