background hepatitis b virus (hbv) is one of the most common chronic viral infections in the world. iran has a low to intermediate hbv prevalence and approximately 1.5 million people are living with hbv infection. the impact of hbv in iran is unknown and given the very low levels of alcohol consumption, this region provides an opportunity to examine the impact of isolated chronic hbv infection....

The authors examine some recently proposed criteria for determining when to adjust for covariates related to misclassification, and show these criteria to be incorrect. In particular, they show that when misclassification is present, covariate control can sometimes increase net bias, even when the covariate would have been a confounder under perfect classification, and even if the covariate is ...

Confounding is a basic problem of comparability – and therefore has always been present in science. Originally a plain English word, it acquired more specific meanings in epidemiologic thinking about experimental and non-experimental research. The use of the word can be traced to Fisher. The concept was developed more fully in social science research, among others by Kish. Landmark developments...