Less than optimum strategies for missing values can produce biased estimates, distorted statistical power, and invalid conclusions. After reviewing traditional approaches (listwise, pairwise, and mean substitution), selected alternatives are covered including single imputation,multiple imputation, and full information maximum likelihood estimation. The effects of missing values are illustratedf...

Agile software development (ASD) methods were introduced as a reaction to traditional software development methods. Principles of these methods are different from traditional methods and so there are some different processes and activities in agile methods comparing to traditional methods. Thus ASD methods require different measurement practices comparing to traditional methods. Agile teams oft...

Background Peripherally inserted central catheter tip placement at the cavoatrial junction is associated with reduced catheter-related deep vein thrombosis. Electrocardiographic confirmation purportedly improves accuracy of placement, but whether this approach can reduce thrombosis unknown. Methods Prospectively collected data from patients that received peripherally catheters 52 Michigan hospi...