In epidemiology, Information bias refers to bias arising from measurement error. Information bias is also referred to as observational bias and misclassification. A Dictionary of Epidemiology, sponsored by the International Epidemiological Association, defines this as the following: “1. A flaw in measuring exposure, covariate, or outcome variables that results in different quality (accuracy) of information between comparison groups. The occurrence of information biases may not be independent of the occurrence of selection biases.