There is not a single pharmaceutical that halts or even slows any neurodegenerative disease. Mounting evidence shows that prions cause many neurodegenerative diseases, and arguably, scrapie and Creutzfeldt-Jakob disease prions represent the best therapeutic targets. We report here that the previously identified 2-aminothiazoles IND24 and IND81 doubled the survival times of scrapie-infected, wil...

In 1986 the International Journal of Epidemiology published "Identifiability, Exchangeability and Epidemiological Confounding". We review the article from the perspective of a quarter century after it was first drafted and relate it to subsequent developments on confounding, ignorability, and collapsibility.

I read with interest the article on computerized tests to evaluate psychomotor performance in children with specific learning disabilities (SpLD) by taur and colleagues1. the study was conducted with the aim to compare the performance on a battery of six psychomotor tests of children with SpLD and those without any learning disabilities (controls) using computerized tests. the authors deserve c...

To the Editor:—I read the study by Fellahi JL et al. titled “Perioperative use of dobutamine in cardiac surgery and adverse cardiac outcome” with great interest. This study showed that the use of dobutamine was associated with adverse outcomes in adult cardiac surgery, and the authors concluded that these results suggest that dobutamine should only be administered when the benefit is judged to ...

The development of novel nanomaterials with unique physico-chemical properties is increasing at a rapid rate, with potential applications across a broad range of manufacturing industries and consumer products. Nanomaterial safety is therefore becoming an increasingly contentious issue that has intensified over the past 4 years, and in response, a steady stream of studies focusing on nanotoxicol...

Introduction In epidemiologic research, it is essential to avoid bias, to control confounding and to undertake accurate replication. Bias, confounding and random variation/chance are the non-causal reasons for an association between an exposure and outcome. These major threats to internal validity of a study should always be considered as alternative explanations in the interpretation. Bias is ...

Correspondence: [email protected] Department of Decision Sciences, HEC Montréal, 3000 chemin de la Côte-Sainte-Catherine, H3T 2A7 Montréal, Canada Abstract Rank correlation is invariant to bijective marginal transformations, but it is not immune to confounding. Assuming a categorical confounding variable is observed, the author proposes weighted coefficients of correlation for continuous variable...

1 Milo Schield, ([email protected]) has taught statistics and statistical literacy for over 20 years at Augsburg College in Minneapolis, MN. With a BS from Iowa State, an MS from the University of Illinois and a Ph.D. from Rice University he has pursued a variety of professional interests including Operations Research at a large property-casualty insurance company. Milo is the Director of th...

Non-identifiability of parameters is a well-recognized problem in classical statistics, and Bayesian statisticians have long recognized the importance of exchangeability assumptions in making statistical inferences. A seemingly unrelated problem in epidemiology is that of confounding: bias in estimation of the effects of an exposure on disease risk, due to inherent differences in risk between e...

a confounder is a variable whose presence affects the variables being studied so that the results do not reflect the actual relationship. there are various ways to exclude or control confounding variables including randomization, restriction and matching. but all these methods are applicable at the time of study design. when experimental designs are premature, impractical, or impossible, resear...