This commentary presents the case against housing rats and mice in laboratory cages; the commentary bases its case on their sentience, natural history, and the varied detriments of laboratory conditions. The commentary gives 5 arguments to support this position: (a) rats and mice have a high degree of sentience and can suffer, (b) laboratory environments cause suffering, (c) rats and mice in th...

statistical errors are common in scientific literature and about 50% of the published articles have at least one error. the assumption of normality needs to be checked for many statistical procedures, namely parametric tests, because their validity depends on it. the aim of this commentary is to overview checking for normality in statistical analysis using spss.

the topic of how cost-effectiveness information informs priority setting in healthcare remains important to both policy and practice. this commentary considers the study carried out by eckard and colleagues in sweden. in it we distinguish between the conditions at national and local levels and put forward some recommendations for research into local priority setting in particular.

Estimating the independent effect of ‘‘place’’ on health outcomes has proven quite difficult. In this issue of the Journal, Auchincloss and Diez Roux contribute a lucid introduction to agent-based simulation models and argue that they may be a fruitful alternative to current approaches to the problem. Insofar as conceptual understanding must precede empirical investigation, this author agrees. ...

An association between air pollution and hospital admission for heart failure was first noted in the literature in 1995 (1). The association was confirmed in subsequent studies (2, 3), along with many studies showing an association with a more general increase in cardiovascular admissions (4–6). The most consistent associations have been with carbon monoxide and particulate matter, and both Poi...

Positivity, or the experimental treatment assignment assumption, requires that there be both exposed and unexposed participants at every combination of the values of the observed confounders in the population under study. Positivity is essential for inference but is often overlooked in practice by epidemiologists. This issue of the Journal includes 2 articles featuring discussions related to po...

Ullman and colleagues should be congratulated for an energetic assault on some of the core issues in neurolinguistics. This work attempts to detect an impact of productivity differences in morphology upon fluency differences in aphasia. This basic goal is well-motivated empirically and should eventually succeed. However, I believe that the links currently being proposed between language and the...

The analytic approaches used in nutritional epidemiology for dietary pattern analyses share common characteristics with those of genetic epidemiology. In this issue of the Journal, Gorst-Rasmussen et al. (Am J Epidemiol. 2011;173(10):1097–1104) discuss one such approach. Application of methods used in genetic pattern analyses to nutritional epidemiology could prove valuable but raises important...