Nephron Clinical Practice 

Abstract: Though simple and attractive, the role of hydration for the prophylaxis of contrast nephrotoxicity has not been definitively established. We prospectively evaluated the role of deliberate saline hydra

Abstract: Chronic diseases present a significant challenge to 21st century global health policy. In developing nations, the growing prevalence of chronic diseases such as chronic kidney disease has severe implications on health and economic output. The rapid rise of common risk factors such as diabetes, hypertension, and obesity, especially among the poor, will result in even greater and more profound burdens that developing nations are not equipped to handle. Attention to chronic diseases, chronic kidney disease in particular, has been lacking, largely due to the global health community's focus on infectious diseases and lack of awareness. There is a critical need for funding in and to developing countries to implement more comprehensive, cost-effective, and preventative interventions against chronic diseases. This paper examines the epidemiology of chronic diseases, the growing prevalence of chronic kidney disease and its implications for global public health, and the associated health and economic burdens. Finally, a summary review of cost-effective interventions and funding needs is provided.

Abstract: Cohort studies form a suitable study design to assess associations between multiple exposures on the one hand and multiple outcomes on the other hand. They are especially appropriate to study rare exposures or exposures for which randomization is not possible for practical or ethical reasons. Prospective and retrospective cohort studies have higher accuracy and higher efficiency as their respective main advantages. In addition to possible confounding by indication, cohort studies may suffer from selection bias. Confounding and bias should be prevented whenever possible, but still can exert unknown effects in unknown directions. If one is aware of this, cohort studies can form a potent study design in nephrology producing, in general, highly generalizable results.

Abstract: The internal validity of an epidemiological study can be affected by random error and systematic error. Random error reflects a problem of precision in assessing a given exposure-disease relationship and can be reduced by increasing the sample size. On the other hand, systematic error or bias reflects a problem of validity of the study and arises because of any error resulting from methods used by the investigator when recruiting individuals for the study, from factors affecting the study participation (selection bias) or from systematic distortions when collecting information about exposures and outcomes (information bias). Another important factor which may affect the internal validity of a clinical study is confounding. In this article, we focus on two categories of bias: selection bias and information bias. Confounding will be described in a future article of this series.